types of problem solving mcat

Thinking and problem solving.

Duncker’s candle problem is a classic test for functional fixedness. The solution is to empty the box of thumbtacks, put the candle into the box, use the thumbtacks to nail the box (with the candle in it) to the wall, and light the candle with the match. The concept of functional fixedness predicts that the participant will only see the box as a device to hold the thumbtacks and not immediately perceive it as a separate and functional component available to be used in solving the task.

• Problem solving refers to a state of desire for reaching a definite goal from a present condition that either is not directly moving toward the goal, is far from it, or needs more complex logic for finding a missing description of conditions or steps toward the goal.
• A mental set refers to the phenomenon of becoming stuck on a specific problem-solving strategy, a type of rigidity that inhibits the ability to generate alternatives.
• Rigidity refers to inability to modify concepts and attitudes once developed. A specific example of rigidity is functional fixedness , which is a difficulty conceiving new uses for familiar objects.
• Duncker's candle problem is a classic cognitive performance test, measuring the influence of functional fixedness on a participant's problem solving capabilities.
• Trial-and-error is a fundamental method of solving problems. It is characterized by repeated, varied attempts which are continued until success, or until the agent stops trying.
• Deductive reasoning is the process of reasoning from one or more statements (premises) to reach a logically certain conclusion.
• Inductive reasoning is reasoning that derives general principles from specific observations.

Scientific Inquiry & Reasoning Skills: Overview

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Leaders in medical education believe that tomorrow’s physicians need to be able to combine scientific knowledge with skills in scientific inquiry and reasoning. With that in mind, the MCAT ® exam will ask you to demonstrate four scientific inquiry and reasoning skills that natural, behavioral, and social scientists rely on to advance their work. The four scientific inquiry and reasoning skills listed below will be tested on three sections of the exam:

Chemical and Physical Foundations of Biological Systems Section

Biological and Biochemical Foundations of Living Systems Section

Psychological, Social, and Biological Foundations of Behavior Section

Knowledge of Scientific Concepts and Principles

Demonstrating understanding of scientific concepts and principles

Identifying the relationships between closely-related concepts

Scientific Reasoning and Problem-Solving

Reasoning about scientific principles, theories, and models

Analyzing and evaluating scientific explanations and predictions

Reasoning about the Design and Execution of Research

Demonstrating understanding of important components of scientific research

Reasoning about ethical issues in research

Data-Based and Statistical Reasoning

Interpreting patterns in data presented in tables, figures, and graphs

Reasoning about data and drawing conclusions from them

Scientific Inquiry & Reasoning Skills - Skill 1

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Scientific Inquiry & Reasoning Skills - Skill 2

Scientific Reasoning and Problem-solving

Scientific Inquiry & Reasoning Skills - Skill 3

Scientific inquiry & reasoning skills - skill 4.

Data-based Statistical Reasoning

Scientific Inquiry & Reasoning Skills

• General Mathematical Concepts and Techniques

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• Foundational Concept 1
• Foundational Concept 2
• Foundational Concept 3
• Foundational Concept 4
• Foundational Concept 5
• Foundational Concept 6
• Foundational Concept 7
• Foundational Concept 8
• Foundational Concept 9
• Foundational Concept 10

Critical Analysis and Reasoning Skills Section

• Skill 1: Foundations of Comprehension
• Skill 2: Reasoning Within the Text
• Skill 3: Reasoning Beyond the Text
• Passage Types
• Skill 1: Knowledge of Scientific Principles
• Skill 2: Scientific Reasoning and Problem-solving
• Skill 3: Reasoning about the Design and Execution of Research
• Skill 4: Data-based Statistical Reasoning

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Problem-Solving

Psychology & Sociology

Some mental processes involve analyzing and answering problems by using techniques like trial and error , where repeated varied attempts are made without a systematic approach, and algorithms , which consist of step-by-step processes that eventually yield the correct answer. Other key aspects of problem-solving involve deductive reasoning , which is forming specific conclusions based on generally accepted truths, and inductive reasoning , which draws general conclusions from specific premises. However, some obstacles can impede problem-solving, such as having an entrenched mental set , or the tendency to approach similar problems in familiar ways, and functional fixedness , which is the inability to see an object's use beyond its traditional purpose.

Lesson Outline

<ul> <li>Introduction to problem-solving</li> <li>Types of problem-solving</li> <ul> <li>Trial and error: Repeated varied attempts without a systematic approach</li> <li>Algorithm: Step-by-step processes eventually resulting in the correct answer</li> <li>Deductive reasoning: Forming specific conclusions based on general statements or rules</li> <li>Inductive reasoning: Drawing general conclusions from specific premises</li> </ul> <li>Problem-solving obstacles</li> <ul> <li>Mental set: Tendency to approach similar problems in familiar ways</li> <li>Functional fixedness: Inability to see an object's use outside its traditional function</li> </ul> </ul>

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What are the key differences between deductive and inductive reasoning in problem-solving?

Deductive reasoning involves drawing specific conclusions based on general principles or premises that are accepted to be true. For example, all pigs have snouts. Hamlet is a pig. Therefore, Hamlet has a snout. Inductive reasoning, on the other hand, involves reaching general conclusions based on specific observations. An example of inductive logic is the first two pigs in the barn are pink, therefore, all pigs in the barn are pink

How can trial and error be used effectively for problem-solving?

Trial and error can be an effective problem-solving strategy when you're dealing with unknown variables. Without any systematic approach, one can arbitrarily test different variables or conditions and observe patterns or results that may lead to a solution. For example, someone could arbitrarily listen to different types of music to determine one they might enjoy.

What is the role of algorithms in problem-solving?

An algorithm is a step-by-step procedure to solve a problem or complete a task. An algorithm might be a series of tests or procedures applied systematically. Using an algorithm may help to ensure consistent results and reduces the likelihood of missing critical information or making errors in the identification process.

How can functional fixedness and mental set hinder problem-solving?

Functional fixedness is the inability to see alternative uses for an object or tool, while mental set is the tendency to continue solving a problem using a familiar approach even when it's no longer the most efficient or effective method. Both of these cognitive biases can hinder problem-solving by limiting creativity and flexibility in approaching new challenges or unfamiliar scenarios. Overcoming functional fixedness and mental set involves practicing divergent thinking, considering different perspectives, and remaining open to alternative solutions and ideas.

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How to take a systematic approach to problems on the MCAT 

Before I went to college, I was professional ballet dancer and I loved to practice pirouettes—turning around on the tiptoes of one foot.  One of the first things I learned about pirouettes is that if I tried something completely different in my technique every time I practiced, I wouldn’t improve. Occasionally I would get lucky and do a few more pirouettes, but it never stuck, and I always regressed back to where I had been. I thought I was just bad at pirouettes in some intrinsic way, the way many of my students claim they are “bad test-takers.”

But when I was 15, I had a sharp teacher that told me to stop trying so many things. “Try one way of doing things for a while, make sure you can do that consistently, and then make small changes to see if they help.” The progress was slow, but consistent, and learning to approach my technique this way was a large part of why I was able to become a professional ballet dancer—and do quite well on the MCAT.

For this reason, I take a systematic approach to solving problems on the MCAT. When I miss problems (which these days is in medical school, not on the MCAT) I am able to look back at my process and see exactly what went wrong, and figure out the best way forward to prevent missing similar problems in the future. In other words, by having a systematic approach, every wrong answer provides specific actionable feedback.  Below is an explanation of a basic approach and two of the things I ask my students to do when doing practice problems.

Basic approach

Initially, I teach my students to read the passage, (take notes if doing CARS, more on that in a different post) read the problem’s question, and then assess the answer choices one at a time for truth and relevance in an active question-driven fashion, until only the correct answer remains.

In analyzing an answer choice, I ask my students to have an explicit guiding question. Here are some examples: Is X true? Does Y follow X?  Is X indicated in the passage? There are many permutations of questions based on the answer choice, but the fundamental point is that students need to be actively looking in either the passage or their memory of specific evidence in favor of the answer choice or specific evidence against the answer choice. (For my rationale behind requiring specific justification, see my post on Total Justification). By having a specific, even if simple, question to guide the student in assessing the truth of an answer choice, students prevent against the rambling purposeless assessment of the passage which is so common among MCAT test-takers.  

Answer choices have to be correct in terms of reflecting either the knowledge being tested (biology, chemistry, physics, psychology, social science etc…).  There are two primary places a test-taker can draw from when assessing the truthfulness of an answer choice: the passage or memory. I teach my students to go to the passage first (with a question-guided approach) for two reasons: first, often the information is in the passage, and even if not, often the passage attaches conditions or important context to information that must be drawn from memory. If there is no helpful information in the passage, then I will let my students use their memory. I recommend this sequence of sources of information because in my experience, most students over-rely on their content-studying to answer questions and miss problems that have answer choices that are true in the abstract but not in the given situation of the passage.

2. Relevance

Simply put, does the answer choice correctly answer the question? Many answer choices are true in and of themselves but don’t correctly answer the question.  A common mistake among MCAT test-takers is to pick answers that reflect real phenomena, but don’t actually address the question. By specifically addressing relevance, we can guard against that mistake. I really like this paragraph.

Let’s pretend the MCAT gives us a nice long passage saturated with information about the excretory system and explains that a common medication- Furosemide, acts by inhibiting the Na/K/Cl transporter in the thick ascending limb of the loop of Henle, which transports those ions out of the lumen of the nephron and into the interstitium. For this reason, Furosemide can be used to reduce blood pressure. Here is a possible question:

How does Furosemide directly affect blood pressure?

• Furosemide acts on receptors in vascular smooth muscle to cause vasoconstriction.
• Furosemide acts on hepatocytes to decrease ion reabsorption allowing increased secretion of water.
• Furosemide reduces the osmotic pressure differential across in wall of the nephron
• Furosemide reduces Vitamin K absorption thereby inhibiting the coagulation cascade.

Below as are analyses of this question in terms of truth and relevance.  

Truth: Does Furosemide act on smooth muscle cells? That’s beyond the scope of the MCAT, so we don’t have to assess that. The MCAT commonly includes information that test takers are not expected to know; learning to recognize that is essential.

Relevance: Would vasoconstriction explain how Furosemide lowers blood pressure (as stated in the last sentence of the passage)? No, part of basic MCAT biology is the vasoconstriction, or reducing the radius of blood vessels increases the pressure on the vessel walls, which means there is increased blood pressure. Thus, even if Furosemide does act this way on vascular smooth muscle (it doesn’t) it would be irrelevant to the passage and question, and could be eliminated.

Truth : Does Furosemide act on hepatocytes: Not indicated in the passage. The passage indicates that Furosemide acts on nephrons, which are in the kidney, not the liver. Furthermore, test takers should know that the Kidney is the primary organ regulating blood pressure as opposed to the liver. Thus we can cross off this answer.

Relevance : Normally I don’t recommend assessing relevance if we have already determined that the answer choice is untrue, but in this case, we should acknowledge that while untrue, the increasing water secretion would lower blood pressure, so this answer choice is relevant.

Truth : A knowledgeable test taker familiar with both the kidney and osmotic pressure will recognize that by inhibiting the ion transporter indicated in the passage, there is less transport of ions out of the nephron tubule and therefore a reduced osmotic pressure differential. Thus this answer choice is true.

Relevance : Does reducing the osmotic pressure differential explain how Furosemide lowers blood pressure? Yes, if there is less osmotic pressure forcing water out of the nephron and back into circulation, the kidney is then excreting more water, which would reduce the volume of blood in the body and thus lower blood pressure. This answer is relevant in addition to being true, and therefore is the correct answer.

Truth : while the effect of Furosemide on Vitamin K absorption is beyond the scope of the MCAT, knowing that Vitamin K is involved in the clotting cascade is testable information, and thus one might think this answer choice is true, and not be unreasonable. (It so happens that Furosemide does not affect Vitamin K absorption.)

Relevance : The coagulation cascade has doesn’t affect blood pressure. This answer choice is irrelevant.

Problems with Truth

With this approach, my students can tell me if they are missing problems because they can’t correctly assess the truth of an answer choice. This may mean they need to study specific content in a targeted manner, practice reading graphs and figures, or perhaps they need more practice in applying passage details to answer choices. By classifying missed answers in this way, clear paths forward to improve are easily revealed.  

Problems with relevance

Problems with relevance can manifest for a variety of reasons, but often because students don’t completely understand how the problem relates to the passage and (if not in the CARS section), how that passage relates to the content they have studied. This reflects a failure to discern what is important and then strategically apply knowledge to the problem. Fixing this type of error requires practice and often guidance by a teacher or a tutor in how to approach certain types of problems.  

Above is a simple way to approach MCAT problems that allows for specific actionable feedback on incorrect answers. However, as this is not the only way to look at MCAT problems and in the future, I will be writing additional posts on more nuanced and flexible methods to approach problems. That said, even when using different approaches, there should still be a solid and planned approach so that one’s mistakes can be improved upon in a consistent fashion.

Related Content

MCAT Guide 2024

The majority of U.S. medical schools, as well as many Canadian schools, require you to submit exam scores for the Medical College Admission Test (MCAT) as part of the application progress; our MCAT Guide will provide you with all the information you need for registering, preparing for and completing the MCAT exam in 2024.

What is the MCAT?

The MCAT exam, developed and administered by the Association of American Medical Colleges (AAMC) , is a standardized, multiple-choice examination, designed to support the medical school admission process through the assessment of prerequisites for the study of medicine.

What is tested on the MCAT?

The exam assesses your problem solving and critical thinking skills, and knowledge of natural, behavioral and social science concepts and principles.

MCAT sections

The current version of the MCAT exam – used since April 2015 – assesses candidates across the following four sections:

Chemical and Physical Foundations of Biological Systems

Critical analysis and reasoning skills (cars), biological and biochemical foundations of living systems, psychological, social, and biological foundations of behavior.

You can find more information about each section of the MCAT exam in the MCAT format and MCAT test syllabus sections below.

For information about the MCAT scoring system, including the scoring range and MCAT percentiles, visit our ‘what is a good MCAT score?’ blog.

MCAT format

As mentioned above, the MCAT exam is separated into four sections, each with the following format:

Chemical and Physical Foundations of Biological System

• Time: 95 minutes
• Total number of questions: 59
• Format of questions: 10 passage-based sets of questions, with 4-6 questions per set, and 15 independent questions
• Time: 90 minutes
• Total number of questions: 53
• Format of questions: 9 passage-based sets of questions, with 5-7 questions per passage

The Critical Analysis and Reasoning Skills (CARS) section requires you to apply your comprehension and analysis skills to passages relating to a wide range of disciplines in social sciences and humanities. However, no specific subject knowledge is required within this section of the MCAT. For more information check out our CARS for the MCAT guide.

The other three sections – Chemical and Physical Foundations of Biological Systems; Biological and Biochemical Foundations of Living Systems; Psychological, Social, and Biological Foundations of Behavior – require you to combine your scientific knowledge with scientific inquiry and reasoning skills. You’ll need to draw upon your knowledge of general and organic chemistry, and introductory physics, biology, biochemistry, psychology and sociology.

MCAT test dates

MCAT exam dates are available between January and September at hundreds of Pearson VUE testing centers within the U.S., Canada and select locations throughout the world.

The following are the upcoming 2024 MCAT test dates, booking deadlines and score release dates for U.S. testing centers:

Note: all deadlines are at 11:59 p.m. local test center time and scores are released by 5:00 p.m. ET on the scheduled date.

The 10 Day Deadline is the last date on which you can schedule, reschedule or cancel a reservation, or make amendments to your registration information, for example name or address.

How much does the MCAT cost?

For all 2024 testing dates the registration fees are:

If you’re testing outside of the US, Canada or US Territories you’ll also be charged an additional $120 non-refundable, international fee. You can find more information about the MCAT fees, including rescheduling and cancellation fees, in the MCAT Scheduling Fees section .

You can also take the MCAT in the following locations:

• Puerto Rico
• U.S. Virgin Islands
• China: Hong Kong
• South Africa
• United Kingdom

For MCAT dates, scheduling deadlines and score release dates, follow the relevant link below:

• U.S. territories and international locations

MCAT Registration dates

Scheduling for January – June 2024 test dates will then open on October 24 or 25, 2023, depending on your preferred test center location. For more information visit the AAMC’s website here .

How long is the MCAT?

The AAMC provides the following overview of the expected test day schedule:

The standard start times for MCAT exams are 7:30 a.m. and 3:00 p.m. (local test-center time).

MCAT essentials

You can find more information about the test day on the ‘MCAT test day’ section of the AMMC’s website and MCAT Essentials for Testing Year 2024 ; including the following:

• Test day rules
• Check-in rules and procedures – verification of ID, digital signature, palm vein scan and photo capture
• Information relating to testing with accommodations
• Items allowed in the testing room and during breaks
• MCAT test date noteboard booklet

How many times can you take the MCAT?

There are limits on the number of times you can take the MCAT exam. In a single testing year you can take the exam up to three times . Within a two year period you’re allowed to take the exam four times . And the MCAT can be taken a total of up to seven times in a lifetime .

Remember that voids and no-shows count toward your lifetime limits.

MCAT test syllabus

As you can see from the test format section, there are four multiple choice test sections within the MCAT. You can find a breakdown of the content and assessment for each section, including the level at which each topic is assessed, as well as the disciplines, foundational concepts and scientific inquiry and reasoning skills assessed, within the ‘what’s on the MCAT exam?’ section of the AAMC’s website.

The following is an overview of the syllabus for each:

The AAMC outlines that you’ll be assessed on the following:

• Your ability to solve problems by combining your knowledge of chemical and physical foundational concepts with scientific inquiry and reasoning skills
• Your understanding of the mechanical, physical, and biochemical functions of human tissues, organs, and organ systems
• Your knowledge of basic chemical and physical principles that underlie the mechanisms operating in the human body
• Your ability to reason about and apply your understanding of these basic chemical and physical principles to living systems
• Your ability to solve problems through the combination of biological and biochemical conceptual knowledge and scientific inquiry and reasoning skills
• The processes that are unique to living organisms
• How cells and organ systems within an organism act in order to accomplish these processes
• Your ability to reason in relation to these processes at various levels of biological organization within a living system

In addition to this, both Chemical and Physical Foundations of Biological Systems and Biological and Biochemical Foundations of Living Systems sections are designed to assess the following:

• Biology, organic chemistry and inorganic chemistry, and physics concepts
• Biochemistry concepts
• Cellular and molecular biology topics
• Basic research methods and statistics concepts
• Your scientific inquiry and reasoning, research methods, and statistics skills as applied to the natural sciences
• Psychology, sociology, and biology concepts
• Biology concepts that relate to mental processes and behavior
• Your ability to solve problems by combining your knowledge of foundational concepts with your scientific inquiry and reasoning skills
• Your understanding of the influence of psychological, social, and biological factors
• Your scientific inquiry and reasoning, research methods, and statistics skills as applied to the social and behavioral sciences

This section of the exam differs from the others, requiring you to critically analyze passages of information. It aims to assess your ability to comprehend what you have read, as well as the analysis and reasoning skills required for medical school.

The passage content may be related to ethics, philosophy, studies of diverse cultures, population health, and a wide range of social sciences and humanities disciplines; with a 50/50 split between humanities and social sciences. These passages are relatively short – approximately 500-600 words – but are described as ‘complex, often thought-provoking pieces of writing with sophisticated vocabulary and, at times, intricate writing styles’.

No specific knowledge or understanding is required for this section of the exam, as all of the information will be provided in the passages and questions; however, you will still need to prepare for it to ensure that you perform well. You can find more information in our CARS for the MCAT guide.

Prepare for the MCAT

To support you to prepare effectively for the MCAT exam, you may find it useful to consider the following:

• Creating a study plan Spending time creating a detailed study plan, outlining when and what you will study, will not only guarantee that you allow yourself adequate time to prepare for the exam, but also ensure that your revision time is focused and therefore more productive. The AAMC offers a free resource – ‘how to create a study plan for the MCAT exam’ – which will support you with this.
• Dedicating time to understanding the requirements of the exam To be able to prepare for the MCAT exam you need to be aware of what each section will assess. The MCAT syllabus section above and the ’what’s on the MCAT exam?’ section of the AAMC’s website outline the content of the MCAT exam.
• Familiarizing yourself with the exam features During your preparations, including practice with the exam features and functions will ensure that you’re confident with these, which will potentially save you time during the exam. The AAMC offers a sample test which has the same features and functionality as the MCAT exam; this is useful for gaining experience of these, however, as it doesn't provide a scaled score for the exam it does have its limitations as a practice exam.
• Exploring what resources are available Using quality resources will enhance your MCAT preparations and support you to perform as well as possible during the exam. In addition to the wealth of information on the AAMC’s website (linked throughout the post), which will ensure that you’re familiar with the demands of the exam, practice questions and mock exams are the ideal resource to support your MCAT preparations.

MCAT practice questions

Practice questions and mock exams are the most valuable resource during your MCAT preparations. They’ll ensure that you’re familiar with the types of questions you’ll be asked during the exam, provide you with the opportunity to practice applying your knowledge and developing responses, and become accustomed to dealing with the time pressures and demands of the exam.

To make effective use of practice questions, you should aim to utilize them to identify areas which you need to improve, so you can focus on developing further and performing better within the exam. Quality practice questions will also provide you with feedback so you can continue to learn from your mistakes and identify further learning needs.

Coming soon…

This is where our artificial intelligence powered, adaptive question bank will help you to take your MCAT preparations to the next level. Using state of the art algorithms, it identifies your strengths and weaknesses, tailoring questions to your learning needs and ensuring that you focus on your areas for development. A question bank which helps you to make more effective use of your MCAT preparation time and progress your learning

Apps for MCAT studying

Our question bank will also be available as a web app, meaning you can access practice questions and tests on the go, allowing you to squeeze in some MCAT revision whenever you have the opportunity.

For more guidance on applying, preparing and undertaking the MCAT exam, visit the MCAT section of our website, where you’ll find useful blog posts – sharing a ‘MCAT Checklist’, ‘What is a Good MCAT Score?’ and the ‘Differences between the MCAT and UCAT’ – and access to our adaptive MCAT question bank with thousands of professionally written practice questions and tests.

We’ll keep you updated

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All You Need to Know: MCAT Solutions and Gases

The MCAT, the entrance exam for aspiring medical professionals, demands a strong foundation in various scientific disciplines, including chemistry. Among these, understanding solutions and gases plays a crucial role in the Chemical and Physical Foundations of Biological Systems section. Mastering these concepts equips you to tackle problems related to:

• Biochemical reactions: Many biological processes occur in aqueous environments (solutions) and involve the interaction of various molecules.
• Physiological phenomena: Gas exchange in the lungs, blood pressure regulation, and cellular respiration are all examples of processes that rely on an understanding of gas behavior.
• Pharmacology: Drug delivery and action often depend on the properties of solutions and gas interactions with biological systems.

This comprehensive guide aims to equip you with a thorough understanding of key concepts, problem-solving strategies, and high-yield terms related to solutions and gases in the context of the MCAT.

Throughout this article, we will delve into:

• The fundamentals of solubility and how it governs the behavior of solutes in solutions.
• Different concentration units quantify the amount of solute present in a solution.
• Colligative properties and their influence on solutions, relevant to various biological processes.
• The ideal gas law and its derivatives, allow you to analyze the behavior of gases under various conditions.
• Solubility equilibria and their role in understanding the dynamic nature of solutions.
• The common ion effect and its implications for predicting the solubility of ionic compounds.

By comprehensively exploring these topics and engaging with practice problems, you will gain the confidence and knowledge necessary to excel in the Chemical and Physical Foundations of Biological Systems section and approach the MCAT with a strong foundation in solutions and gases.

Mastering the Chemistry/Physics Section I Jack Westin MCAT

Understanding Solubility and Its Applications in the MCAT

Overview of solubility and its relevance in mcat.

The MCAT frequently assesses your understanding of solubility , which refers to the ability of a substance (solute) to dissolve in another substance (solvent) to form a homogeneous mixture (solution). Knowing the principles of solubility is crucial for interpreting various biological and chemical phenomena relevant to the exam.

Understanding Solubility Rules

Predicting the solubility of ionic compounds is a key skill tested on the MCAT. Fortunately, there are established solubility rules that provide guidelines based on the cation (positive ion) and anion (negative ion) of the compound. These rules help you quickly identify:

• Soluble ionic compounds : These compounds readily dissolve in water to form clear solutions.
• Insoluble ionic compounds: These compounds have limited solubility in water and form precipitates (solids that settle out of the solution).

By memorizing and understanding these rules, you can efficiently predict the solubility of various ionic compounds encountered on the MCAT.

Concentration Units: Exploring Different Units Used to Express Concentration

Quantifying the amount of solute dissolved in a solution is essential for various applications. The MCAT often involves problems requiring you to understand and utilize different concentration units :

• Molarity (M): This unit expresses the moles of solute per liter of solution . It tells you how many moles of a substance are dissolved in one liter of the solution.
• Molality (m): This unit expresses the moles of solute per kilogram of solvent . Unlike molarity, which depends on the total solution volume, molality focuses on the concentration of the solute relative to the pure solvent, making it less susceptible to temperature changes.
• Normality (N): This older unit, less commonly used today, expresses the equivalents of solute per liter of solution . Equivalents are a concept related to the reaction stoichiometry of the solute, which won’t be covered in detail here.

Understanding these units and their applications is crucial for interpreting data and solving problems related to solutions on the MCAT.

Colligative Properties: How Solute Concentration Affects Physical Properties of Solutions

Colligative properties are a group of solution properties that depend solely on the number of solute particles present, not the identity of the particles themselves . In simpler terms, the more solute particles you have dissolved in a solution, the more pronounced these colligative effects become. Some key colligative properties tested on the MCAT include:

• Boiling point elevation: Adding a solute increases the boiling point of the solution compared to the pure solvent.
• Freezing point depression: Adding a solute lowers the freezing point of the solution compared to the pure solvent.
• Osmotic pressure: This property arises when two solutions of different concentrations are separated by a semipermeable membrane, allowing solvent molecules but not solute particles to pass through. Understanding the principles of osmotic pressure is crucial for interpreting various biological phenomena, such as fluid balance in cells.

Grasping these concepts and their connection to concentration units is essential for tackling MCAT problems involving solutions and their properties.

Solubility Equilibria and Reactions

While the previous section explored the fundamentals of solubility, the MCAT often delves deeper into specific phenomena related to solubility and reactions. Here, we explore two key concepts and their applications:

Common Ion Effect: Examining the Impact of Shared Ions on Solubility

The common ion effect describes how the presence of a common ion (an ion shared by both the solute and another added substance) can suppress the solubility of the original solute . Imagine adding salt (NaCl) to a saturated solution of silver chloride (AgCl). Both NaCl and AgCl share the chloride ion (Cl-). Adding more Cl- ions from the salt disrupts the equilibrium between dissolved and undissolved AgCl particles, causing some AgCl to precipitate out of the solution to maintain equilibrium.

Understanding the common ion effect is crucial for solving MCAT problems involving:

• Predicting changes in solubility upon adding solutions containing common ions.
• Explaining how buffers work to maintain a stable pH by resisting changes in hydrogen ion concentration (H+).

Solubility Equilibria: Understanding the Equilibrium Between Dissolved and Undissolved Solutes

When an ionic compound dissolves in water, it reaches a state of equilibrium where the rate of dissolving (dissolving) equals the rate of precipitation (coming out of solution). This equilibrium can be represented by a chemical equation showing the dissolved ions and their corresponding concentrations.

Understanding solubility equilibria is essential for:

• Interpreting solubility product constants (Ksp), which quantify the equilibrium constant for a specific ionic compound dissolving in water.
• Predicting the direction of equilibrium shift (dissolving or precipitation) based on concentration changes.

Application of Solubility Concepts to MCAT Scenarios

The concepts of common ion effect and solubility equilibria are frequently applied to various MCAT scenarios, such as:

• Predicting the effect of adding electrolytes (ionic compounds) on the solubility of other ionic compounds.
• Explaining the role of solubility equilibria in biological processes, such as the formation of kidney stones or the regulation of blood calcium levels.

By mastering these advanced concepts, you can strengthen your understanding of solubility and confidently tackle MCAT problems involving reactions and equilibria. Remember to utilize official MCAT resources and practice problems to solidify your knowledge and apply these concepts to real-world scenarios.

AAMC Practice Help: Chemistry and Physics

Exploring MCAT Gas Law Equations

While understanding the behavior of gases can seem complex, the MCAT relies on a few key gas laws and their applications. This section delves into the fundamental equations governing gases and how they are used to solve MCAT-style problems.

Ideal Gas Law: Introducing the Fundamental Equation and its Components

The ideal gas law is a cornerstone for understanding the behavior of ideal gases (gases that closely follow certain assumptions, such as negligible particle size and interactions). This single equation relates four crucial variables:

• Pressure (P): Measured in units like atmospheres (atm) or Pascals (Pa)
• Volume (V): Measured in units like liters (L) or milliliters (mL)
• Temperature (T): Measured in Kelvin (K)
• Number of moles (n): Represents the quantity of gas particles

The ideal gas law is expressed as:

where R is the ideal gas constant , a constant value that converts between pressure, volume, temperature, and the number of moles. Understanding the relationship between these variables and their units is crucial for solving MCAT problems involving gases.

Ideal Gas Law Derivatives: Exploring Variations and Applications

The ideal gas law can be rearranged to derive other gas laws that focus on specific relationships between the variables. Knowing these derivatives allows you to approach problems from different perspectives:

• Boyle’s Law: This law states that at constant temperature (T) , the pressure (P) of a gas is inversely proportional to its volume (V) . In simpler terms, if you squeeze a gas sample (decrease V), its pressure will increase, and vice versa (keeping temperature constant).
• Charles’ Law: This law states that at constant pressure (P) , the volume (V) of a gas is directly proportional to its absolute temperature (T) . As the temperature increases, the gas expands and its volume increases, and vice versa (keeping pressure constant).
• Gay-Lussac’s Law: This law states that at constant volume (V) , the pressure (P) of a gas is directly proportional to its absolute temperature (T) . In simpler terms, if you heat a gas in a sealed container (constant volume), its pressure will increase, and vice versa.

Understanding these derivatives and how they relate to the ideal gas law equips you to tackle various MCAT problems involving changes in pressure, volume, temperature, and the number of moles of gas.

Partial Pressure: Understanding the Concept and its Role in Gas Mixtures

In real-world scenarios, you often encounter gas mixtures containing different individual gases. Partial pressure refers to the pressure exerted by an individual gas in a mixture, as if it were the only gas present and occupying the entire volume.

Dalton’s Law of Partial Pressures states that the total pressure of a gas mixture is equal to the sum of the partial pressures of its individual components . This concept is crucial for:

• Analyzing the behavior of gas mixtures in various scenarios, such as gas chromatography (a technique used to separate and identify components of a mixture).
• Understanding how changes in the composition of a gas mixture can affect the total pressure.

By mastering these gas law concepts and their applications, you can confidently approach MCAT problems involving the behavior of gases in various contexts. Remember to practice applying these concepts to different scenarios to solidify your understanding and exam readiness.

High-Yield Terms for MCAT Solutions and Gases

Succeeding on the MCAT requires not only understanding core concepts but also familiarity with key terminology used in the exam. This section highlights some high-yield terms related to solutions and gases that you should be comfortable with:

Key Terms and Concepts Crucial for MCAT Success:

• Standard temperature and pressure (STP): Defined as 0°C (273.15 K) and 1 atm, STP serves as a reference point for gas law calculations.
• Ideal gas constant (R): This constant value appears in the ideal gas law equation and relates pressure, volume, temperature, and the number of moles of gas.
• Molarity (M): Represents the moles of solute per liter of solution, a crucial unit for quantifying concentration in solutions.
• Molality (m): Represents the moles of solute per kilogram of solvent, useful for concentration calculations when dealing with solutions that change volume upon temperature changes.
• Solubility product constant (Ksp): This equilibrium constant quantifies the solubility of a specific ionic compound and is helpful for predicting precipitation and dissolution phenomena.
• Colligative properties: These properties of solutions depend solely on the number of solute particles, not their identity, and include boiling point elevation, freezing point depression, and osmotic pressure.
• Partial pressure: Refers to the pressure exerted by an individual gas in a mixture, as if it were the only gas present.

The Importance of These Terms in Solving MCAT Problems:

These terms are not just isolated vocabulary; they represent fundamental concepts that form the basis of numerous MCAT problems. By understanding these terms and their applications, you can:

• Interpret data and problem statements: Recognizing key terms in the context of a problem allows you to identify the relevant concepts and apply the appropriate equations or principles.
• Choose the correct answer choice: Familiarity with the terminology ensures you can distinguish between similar concepts and select the most accurate answer based on the information presented.
• Solve problems efficiently: Understanding the meaning and implications of these terms allows you to approach problems strategically and avoid unnecessary confusion.

Remember, consistently reinforcing your understanding of these high-yield terms through active learning and practice will significantly enhance your confidence and problem-solving skills on the MCAT. Utilize official MCAT resources and practice problems to solidify your understanding and ensure you are well-equipped to tackle exam questions involving solutions and gases.

MCAT Solutions and Gases Passage-Based Questions and Answers

The MCAT frequently presents passage-based questions that require applying your knowledge of solutions and gases to real-world scenarios. This section provides practice with such questions and in-depth explanations to solidify your understanding.

Practice Scenarios Involving Solutions and Gases:

Scenario 1: A patient suffering from kidney stones is undergoing dialysis. The dialysis solution is prepared with a specific concentration of electrolytes to match the patient’s blood. Explain why maintaining the correct concentration of electrolytes in the dialysis solution is crucial.

Scenario 2: A closed container initially holds 2 moles of helium gas at 25°C and 1 atm pressure. The temperature is then increased to 75°C while the volume remains constant. What is the final pressure of the gas?

Step-by-Step Analysis of Passage-Based Questions:

Scenario 1 Analysis:

• Identify the relevant concept: This scenario involves maintaining a specific concentration of solutes (electrolytes) in a solution (dialysis solution).
• Apply knowledge: Remember that colligative properties, like osmotic pressure , depend on the concentration of solutes. If the concentration of electrolytes in the dialysis solution differs significantly from the patient’s blood, it can cause a dangerous imbalance in fluid movement across cell membranes.
• Formulate an answer: Maintaining the correct concentration of electrolytes helps ensure osmotic equilibrium between the patient’s blood and the dialysis solution, preventing unwanted fluid shifts that could harm the patient.

Detailed Answers and Explanations:

Scenario 1 Answer: Maintaining the correct concentration of electrolytes in the dialysis solution is crucial to prevent disruption of osmotic equilibrium between the patient’s blood and the dialysis solution. This imbalance can lead to:

• Fluid shifts: If the concentration in the dialysis solution is too high, water can be drawn out of the patient’s cells, leading to dehydration and cell shrinkage. If it’s too low, water can flow into the cells, causing them to swell and potentially burst.
• Electrolyte imbalances: Disruptions in electrolyte concentration can disrupt various physiological processes, affecting nerve and muscle function, heart rhythm, and blood pressure.

Scenario 2 Answer: We can use the ideal gas law (PV = nRT) to solve this problem. Since volume (V) and the number of moles (n) remain constant, we can rewrite the equation as P₁T₁ = P₂T₂ (where P₁ and T₁ are the initial pressure and temperature, and P₂ and T₂ are the final pressure and temperature).

Plugging in the known values:

• T₁ = 25°C + 273.15 K = 298.15 K
• T₂ = 75°C + 273.15 K = 348.15 K

Solving for P₂:

P₂ = (P₁ × T₂) / T₁

P₂ = (1 atm × 348.15 K) / 298.15 K

P₂ ≈ 1.17 atm

Therefore, the final pressure of the gas is approximately 1.17 atm.

By actively engaging with practice scenarios and understanding the thought process behind each answer, you can develop your problem-solving skills and approach similar questions on the MCAT with confidence. Remember, consistent practice and review are key to mastering these concepts and excelling on the exam.

Standalone MCAT Solutions and Gases Questions and Answers

This section offers standalone practice questions to test your understanding of solutions and gases beyond the passage-based scenarios. Accompanying each question are detailed explanations to solidify your learning and provide insights into effective MCAT problem-solving strategies.

Standalone Questions:

• A solution is prepared by dissolving 0.2 moles of table sugar (C₁₂H₂₂O₁₁) in 500 mL of water. What is the molarity (M) of the solution?
• A gas sample initially occupies 2.0 L at a pressure of 3.0 atm and a temperature of 300 K. If the pressure is increased to 4.5 atm while the temperature remains constant, what is the final volume of the gas?
• When sodium chloride (NaCl) is added to a saturated solution of silver chloride (AgCl), what happens to the solubility of AgCl?

Solutions and Explanations:

• Molarity (M) = moles of solute / liters of solution
• M = 0.2 mol / 0.5 L = 0.4 M

Explanation:

This question tests your understanding of the concentration unit molarity and its formula. Remember to convert the volume from milliliters (mL) to liters (L) for consistency with the unit of molarity.

• We can use Boyle’s Law: P₁V₁ = P₂V₂ (where P₁ and V₁ are the initial pressure and volume, and P₂ and V₂ are the final pressure and volume)
• Since temperature remains constant, T₁ = T₂ and the equation simplifies to P₁V₁ = P₂V₂

This question assesses your ability to apply Boyle’s Law to relate changes in pressure and volume for a gas at constant temperature.

• Adding a common ion (Cl- in this case) from NaCl to a saturated solution of AgCl will suppress the solubility of AgCl due to the common ion effect . This means more AgCl will precipitate out of the solution.

This question tests your knowledge of the common ion effect and its impact on the solubility of ionic compounds.

Tips on Effective Problem-Solving Strategies:

• Identify the relevant concept: Analyze the question and determine the key concept or principle being tested (e.g., molarity, ideal gas law, common ion effect).
• Formulate a plan: Based on the identified concept, choose the appropriate formula, equation, or approach to solve the problem.
• Show your work: Clearly write down the steps you take to reach the solution, including any relevant formulas and calculations.
• Check your answer: Ensure your answer is consistent with the units and the context of the question. Utilize the answer explanations to verify your understanding and identify any errors in your reasoning.

By actively engaging with practice questions and applying these problem-solving strategies, you can strengthen your foundation in solutions and gases and approach MCAT questions with greater confidence and clarity. Remember, continuous practice and review are crucial for success on the exam.

This comprehensive guide has delved into the fundamental concepts of solutions and gases, equipping you with the knowledge and tools necessary to tackle these topics on the MCAT. Let’s recap some key takeaways:

• Master the fundamentals: Grasp the core principles related to solubility, concentration units, gas laws, and their applications.
• Practice diverse question types: Engage with both passage-based and standalone questions to hone your problem-solving skills and critical thinking abilities.
• Solidify your understanding: Actively review explanations, identify areas for improvement, and seek additional resources if needed.

Remember, the MCAT tests your ability to apply your knowledge to real-world scenarios. By consistently practicing and refining your understanding of solutions and gases, you will be well-positioned to approach these topics with confidence and excel on the exam.

Beyond this article, continue your journey by:

• Utilizing official MCAT resources and practice tests provided by the AAMC.
• Consulting relevant textbooks and online resources for in-depth explanations and practice problems.
• Seeking guidance from qualified tutors or mentors who can provide personalized feedback and support.

Mastering solutions and gases on the MCAT is a process of continuous learning and practice. Embrace the challenge, stay curious, and remember that with dedication and perseverance, you can achieve your goals. You can always contact Jack Westin’s team of academic consultants for more tailor-made advice during your MCAT prep journey. Make sure to check out our website for affordable MCAT online courses , tutoring options , free weekly sessions , practice questions , and more!

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Tips from 132 P/S scorer

Hi everyone!

I wanted to make a post about how I scored a 132 in P/S starting from a 125. I had no psychology knowledge and only an intro sociology course (so i had an idea about conflict theory, crime, class and roles, etc.). I did 6 months of prep but I didn't begin scoring 130+ until the last month after I really started grinding P/S. I hope this post can help you out, especially if you are in a similar situation to the one I was in.

Basically, I was doing the MileDown flashcards (110% recommend btw) and trying the 300-pg P/S doc but I wasn't seeing much improvement other than a few points that came from taking numerous exams and practice problems. I started applying the list I am about to give you during my last month of studying and my confidence in P/S (as well as my score) began to improve steadily. Here's everything I did to improve my score.

Use Anki (I recommend MileDown), #1 way to memorize things fo sho. You have to do this every day! No days off.

You should be memorizing word for word definitions of things as well as instances of those things in real life. It sounds tedious, but the more familiar you are with the definition, the more nuanced you can be when choosing between answers on a test.

Make Anki flashcards every time you miss a question. I started doing this the last month of prep and it helped a TON. I have about 250 flashcards from my last month of prep with missed questions / concepts. Here's an example:

Front: Proactive interference is when {{c1::long-term}} memories make it more difficult to form {{c1::new long-term memories.}} [Cloze card]

Back: Sample question:  In a third test, patients are given sentences that contain content related to their lives. These sentences state facts that are either wrong (e.g., “Your niece is named Juliana,” when in fact her name is “Julia”) or distorted somehow. Using such sentences would likely show: proactive interference in the control patients but not in the Korsakoff’s patients. – Patients with Korsakoff's syndrome show difficulty recalling information. So, they likely don't have LTM interference because their LTM is already impaired.

Recognize P/S concepts in your day-to-day life! The P/S section is literally testing how well you know knowledge about how human beings behave at a conscious or subconscious level. Unless you're a hermit in the middle of the woods, these concepts apply to you and everyone you know. The more you envelop yourself in this info and apply it to what you observe, the easier it will come to you on the test.

First of all, don't be annoying about this. I would literally say out loud which concepts I recognized in my day-to-day life, such as when people were using defense mechanisms, or when friends had a Freudian slip. That is NOT necessary. It's just how my brain works lol.

A lot of questions about perception may appear on the MCAT. Notice yourself experiencing motion parallax, or proprioception. Notice examples of signal detection theory, or how your habits are formed by operant conditioning, etc.

I've never seen anyone give this kind of advice out so maybe it works, maybe it doesn't. It's something that I thought worked for me and gave me a deeper understanding of the concepts.

My #1 piece of advice: Watch all the Khan Academy P/S videos . Maybe I should have put this at the beginning of the list but who cares. If you made it this far, this is the gold nugget of this post. If you also hate that forsaken 300 page document / don't know how to use it, watch all the Khan Academy videos. They're somewhat interesting, super easier to understand, and you can watch them at 2x speed and retain most of the info. If I counted my hours correctly, I watched all of the videos over 15 days (non-consecutively) and there's about 18 hours of content (watching at a speed of 1.5x – 2x speed). Some notes about this:

This technique definitely boosted my score from a 128 to a 132. Even a passing familiarity of the videos will give you a decent understanding sufficient for answering more nuanced questions on the exam.

I took notes on only a few of the videos (questions I had frequently missed during practice or concepts which I couldn't wrap my head around). For the most part I didn't take any notes at all or made 1-2 Anki flashcards ( if you're doing the MileDown deck, all of the flashcards come from these videos. So, you won't have to make the really basic flashcards).

Take all of the little quizzes at the end of every section to test your understanding.

I took this advice from a 528 scorer. Listen to the wisdom of the 528 gods

Test-taking strategies

Don't choose an answer choice you don't recognize until you've thoroughly considered the choices you DO know. A majority of the questions I would miss during practice were me choosing a plausible-sounding term rather than a term that I really should know. The trick here is being on point your definitions. Anki will be your best friend here. If you are shaky on your definitions, you will undermine your confidence in the correct choice, which is the one you know.

There will be times when the answer choices you are familiar with aren't the correct ones. In these cases, choose the answer choice that sounds most similar to what is going on in the passage. If the passage is about stereotype threat or aggression or whatever else, choose the answer that best reflects the passage narrative.

If you're really unlucky (like I was) and you get a test question that straight up asks you a question you don't know with no passage context whatsoever, just remain calm. Choose an answer choice which seems plausible to you and just move on. If the concept is actually something that is very nuanced, your exam will be scored to reflect how other students did on that question. If you went through all the KA videos and really grinded your Anki flashcards, it's likely that your answer choice was as good as anybody else's. Don't flag it. Don't stress it. Just get through the rest of the exam!

I say this because there were definitely one or two questions where I made a poor educated guess on my exam, but I still got a 132. I actually know for a fact that there was a question or two that I missed. As I said, the questions were really nuanced or unfamiliar to me despite all of my studying and that was reflected in my final score!

The P/S section is an interesting component of the MCAT and at the beginning of my studying I really didn't understand why I needed to study all of the random-ass words and definitions from fields I never studied. However (especially after applying tip #3), I realized that this section is just as, if not more important than the other components of the exam for a human doctor. The P/S section is a survey of how much you know about what human beings are like, what it's like to be a human, and what humans are capable of as well as their limitations. It describes common elements of the human experience (such as perception, emotion, memory, and cognition) as well as complex differences that form when our experiences interact with the environment/other humans (such as social status, conflict, trauma, race, backstage self, policy, etc.) A week before my test I feel like I finally understood why I spent all of that time studying P/S and appreciated how I might use it if I were a doctor. So if you're studying P/S and feel it might be pointless, just realize that studying this stuff isn't just important for your MCAT score, but also your future career as a medical professional!

Just my two cents.

Hope this helps!

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Piaget's Stages of Cognitive Development

Mcat psychology - chapter 2- section 2 - cognition - cognitive development.

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• Piaget’s Stages of Cognitive Development – MCAT Psychology

Sample MCAT Question - Piaget's Stages of Cognitive Development

In which stage of Piaget’s theory of cognitive development does stranger anxiety develop?

a) Concrete Operational

b) Formal Operational

c) Sensorimotor

d) Pre-operational

C is correct. Stranger anxiety, as well as object permanence, develop during the sensorimotor stage of Piaget’s theory of cognitive development. Answer choice A is incorrect because an understanding of conservation and transformations develop during the concrete operational stage, not stranger anxiety. Answer choice B is incorrect because abstract logic thinking develops during the formal operational stage, not stranger anxiety Answer D is incorrect because pretend play, language development, and egocentrism develop during the preoperational stage, not stranger anxiety.

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Piaget's Stages of Cognitive Development for the MCAT

Cognitive development is the growth and maturation of thinking processes. These processes include reasoning, problem-solving, perceiving, remembering, and imagining. Jean Piaget is the most famous psychologist that has studied cognitive development in children. He believed that children go through four stages of cognitive development, each of which are important to know for the MCAT.

The first of Piaget’s stages is the sensorimotor stage , which takes place from the ages of zero to two. There are two important developmental phenomena in this stage: object permanence and stranger anxiety. 

The second stage is the preoperational stage , which occurs between the ages of two to seven. Children at this stage participate in pretend play, their language develops rapidly, and they exhibit egocentrism. This stage is called preoperational because it occurs before children have mastered operations and certain reasoning skills. 

The third stage is the concrete operational stage , which takes place from the ages of seven to 11. Unlike children in the preoperational stage, children in the concrete operational stage have mastered conservation and transformations but can only understand concrete knowledge. 

The last stage is the formal operational stage , which occurs from the age of 11 and up. In this stage, children are capable of understanding abstract logic and hypothetical situations, not just concrete knowledge.

Let’s go into each of these four stages in more detail.

Stage 1: The Sensorimotor Stage

Piaget’s first stage is called the sensorimotor stage because children in this stage are learning about the world using sensory input and motor behavior. For example, children will grab and shake a rattle to learn that the rattle produces a sound. 

The first important developmental phenomenon in the sensorimotor stage is object permanence , which is the idea that children know an object is present even if they can’t perceive it. One of the most common ways to test object permanence is to place a toy in front of an infant and cover it with a blanket. If an infant has not developed object permanence, when the toy is covered, they will think that the toy has disappeared and will not reach for it. However, if the infant reaches for the toy under the blanket, they have developed object permanence because they understand that the toy is still there. An infant’s response to this test can discern whether or not they have developed object permanence.

Another phenomenon that occurs in this stage is stranger anxiety , which is when a baby exhibits distress and fear upon encountering a stranger. This is because they can’t assimilate strangers’ faces into any of their existing schemas of familiar faces. Since the stranger’s face doesn’t match any familiar faces, the infant doesn’t know what their experience with the stranger will be like, creating feelings of fear and distress. While children in the sensorimotor stage can understand object permanence, they are not yet capable of understanding conservation and transformations, which develops during the preoperational stage.

Stage 2: The Preoperational Stage

The second stage of Piaget’s stages of cognitive development is the preoperational stage, which occurs during the ages of two to seven. During this stage, children learn to think using symbols, but their thinking can be illogical. Pretend play is one way children use symbols in this stage and examples include sword fighting with sticks and pretending to drink out of an empty cup. In these examples, sticks are used as symbols for swords and an empty cup is used as a symbol for a beverage. Another important development during this stage is the rapid development of language. Although children in this stage can understand and speak a language, this doesn’t mean that they have the same level of reasoning and logic as adults.

One developmental phenomenon of this stage is egocentrism , which is when children fail to consider perspectives other than their own. They believe that others perceive a situation in the same way that they perceive a situation. For example, a boy displaying egocentrism may think that a toy car would be a good gift for his sister because he would like the toy himself. He fails to consider that his sister might have different interests than himself. Another example of egocentrism is seen with the Three Mountain Task depicted in Figure 1.

This task is a famous experiment that Piaget developed, where a child is placed in front of a setup with three mountains on a table. Depending on where the child is placed, he will see the mountains from a particular perspective. The child is then asked, “what would someone  else  see if they were standing at a different position?” The child is egocentric if they always say that other people, regardless of their position around the table, will see the same things as he does.

Stage 3. Concrete Operational Stage

The third stage of Piaget’s stages of cognitive development is the concrete operational stage, which ranges from the age of seven to 11. During this stage, children are capable of thinking logically about concrete, or real, events but aren’t able to understand abstract logic. This logical reasoning includes the understanding of conservation and transformations, which is a concept that children in the preoperational stage do  not  understand.

An example of conservation is the conservation of liquids, which is demonstrated in an experiment depicted in Figure 2. A child is presented with two glasses that are the same shape and hold the same amount of water. When asked how the amount of water in these two glasses compare, children in both the preoperational and concrete operational stages are able to say that both glasses hold the same amount of liquid. The child is then presented with a third glass that is narrower with a smaller diameter. The liquid from one of the original two glasses is poured into this narrower glass, and due to its smaller diameter, the liquid will rise up to a higher level. When asked how the amount of water in the glasses compare, children in the preoperational stage will say that there is more liquid in the narrow glass than in the original glass because the liquid in the narrow glass is higher. However, children in the concrete operational stage recognize that the glasses hold the same amount of liquid, despite their differences in liquid height.

Another example of conservation is conservation of number, which is demonstrated in an experiment depicted in Figure 3. Initially, there are a number of coins spread out into two lines. The coins are spaced out evenly, and the experimenter asks the children if one of the lines has more coins than the other. Children in both the preoperational and concrete operational stages can say that both rows have the same number of coins. The experimenter then takes one of the two lines of coins and spreads the coins out. There is no change in the number of coins in this row, and the experimenter asks the children again if one of the lines has more coins than the other. Children in the preoperational stage will think this row now has more coins than the other row just because it is longer. However, children in the concrete operational stage recognize that there is no difference in the number of coins in the lines.

Stage 4. Formal Operational Stage

The last stage of Piaget’s stages of cognitive development is the formal operational stage, which is from the age of 11 and up. During this stage, children can think logically about both concrete events and hypothetical situations. In contrast to the children in the concrete operational stage that can only understand concrete events, children in the formal operational stage can understand abstract ideas.

To illustrate the difference between children in the concrete operational and formal operational stages, children are told that if a glass window is struck with a hammer, the glass window will break. Then, the children are asked what will happen to the window if it is stuck with a hammer. Children in both the concrete operational and formal operational stages will say that the window will break. Next, children are told that if a glass window is struck with a feather, the glass window will break. When the children are asked what will happen to the window if it is struck with a feather, children in the concrete operational stage will say that the window does not break. They are only capable of reasoning with concrete events, and to them, a feather is fluffy and incapable of breaking a glass window. However, children in the formal operational stage are capable of understanding hypothetical situations and abstract logic, so they can correctly respond that the window will break. This example shows that unlike children in the formal operational stage, children in the concrete operational stage can’t understand situations that don’t match their real-world understandings, such as a feather being capable of breaking a glass window. It is the ability to think abstractly and hypothetically that makes this final developmental stage unique.

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Adler & Individual Psychology – MCAT Psychology

Systematic desensitization – mcat psychology, structure of the eye – mcat psychology, erikson’s stages of psychosocial development – mcat psychology.

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MCAT Go Audio Course

Engaging audio learning to take your MCAT learning on the go, any time, any where. You'll be on the way to a higher MCAT score no matter where you are. Listen to over 200+ lessons.

MCAT Practice Exams

Practice makes perfect! Our mock exams coupled with thorough explanations and in-depth analytics help students understand exactly where they stand.

MCAT Prep App

Access hundreds of MCAT videos to help you study and raise your exam score. Augment your learning with expert-created flashcards and a question banks.

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Happy April Fool’s Day from MedSchoolCoach!

While mastering sleep-learning is still a dream, mcat go helps you study for the mcat while you are awake. listen to mcat go for free (a $99 value) by entering your email below to receive an exclusive discount code. this ain’t no joke..