how to do hot and cold water density experiment

Hot and Cold Water Density - Teach Kids How Temperature Effects Water Density

Posted by Admin / in Matter Experiments

An experiment to teach kids about the difference in density between hot and cold water and the natural flow of warmer or cooler water.

Materials Needed

• Two clear cups of equal size
• Index card or wax paper
• Food coloring (2 colors-blue and red)
• Casserole pan

EXPERIMENT STEPS Have an adult help with this experiment since hot water will need to be handled.

Step 1. Place a full cup of water in the freezer or refrigerator and allow it to cool for 15 minutes.

Step 2. Remove the water from the freezer and mix with a few drops of blue food coloring.

Step 3. Heat up a full cup of water. Have an adult help heat the water either in a microwave oven or on the stove. Hot tap water will work it if is very hot. Handle the hot water very carefully.

Step 4. Mix the hot water with a few drops of red food coloring.

Step 5. Place the cold (blue) water cup in the bottom of the casserole pan.

Step 6. Carefully hold the index card on top of the hot (red) water and flip it upside down, resting the cup on top of the cold (blue) water cup. If the cup opening size is larger than an index card, a piece of wax paper will also work for this step, however, if the wax paper stays in contact with hot water too long it will quickly start to stick to the cup.

Step 7. Quickly remove the index card allowing the cold water and hot water to mix. Observe what happens to the different temperature water.

SCIENCE LEARNED

Different temperature water has different density. The normal density of water is 62.4 pounds per cubic foot. Warmer water is less dense and will have a lower weight per cubic foot of space. Colder water is more dense and will weight more for each cubic foot of space. When the index card is removed between the hot and cold water, nothing really happens. The hot water stays elevated above the colder (blue) water. The cold water is more dense than the hot water. The red and blue coloring will stay separated until the water temperatures start to even out. This will actually take quite a while if the very hot and reasonably cold water is used for the experiment. The experiment cannot really be performed with the hot water starting on the bottom. The hot water will rise, but in the process the red food coloring will mix with the blue food coloring in the cold water and result in purple water.

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Hot & Cold Water Science Experiment – Density Science Activity

• September 27, 2020
• Science Videos

This article bring you a science activity video about how differently the density of hot water and cold water.

Courtesy: HooplaKidz Lab (Now known as Lab 360)

Have you ever wondered why the top floors of a multi-story building feel warmer than the bottom floors or the basement? Do you know why oil always floats on water? Well, the answer lies in the difference in density. Hot air is less dense than cooler air, and so hot air rises and makes the upper floors warmer than the lower ones. Oil is also less dense than water, and so it floats. Surprisingly, the difference in density also exists between hot water and cold water, which you could see and confirm yourself by conducting this super fun experiment! 

Steps of the hot and cold water experiment

Word of caution: Make sure to do the experiment under the supervision of parents .

Materials Required 

1 Jar of cold water

1 Jar of hot water 

1 Plastic card 

1 Spoon 

1 Large dish or a baking pan

Red and blue food coloring 

Steps to follow

• Add a few drops of red food color into the hot water jar and stir it cautiously with a spoon. 
• Similarly, add a few drops of blue food color into the cold water jar and stir it with a spoon.
• Now you have a red-colored hot water jar and a blue colored cold water jar. Make sure that water is full up to the top in both the jars. 
• Now, carefully lift the blue colored cold water jar and place it in the dish. Add some more water if some water is spilled during lifting until you see a bulge of water at the rim. 
• Place the plastic or index card carefully onto the top of the blue-colored cold water jar. 
• Next, lift that jar from the dish and turn it upside down. You will notice that there is no need to hold the card with your finger to seal the mouth of the jar. The vacuum formed inside is holding the card in its place. Here, you may need some practice over the sink to do this step. 
• Now take the help of your parent to place the red colored hot water jar in the dish. Carefully place the blue-colored cold water jar on its top. 
• Ask an adult to hold both the jars. Now, gradually pull the card out from the middle. 

Observation 

You will observe that the water of both the jars will slowly mix with each other to form a purple colored mixture. 

• Now, again take a red-colored hot water jar and a blue colored cold water jar. This time, carefully put the index card on the red-colored hot water and turn it upside down just like in step 6. 
• Take the help of your parent to place the blue colored cold water jar in the dish and place the red colored hot water jar on the top of the cold water jar. Gently pull out the plastic card from in-between. 

You will observe that like last time, the reaction of the hot and cold water is different. Both the red and blue colored water is not mixing with each other.

Now from this fun-filled experiment, it is proved beyond any doubt that it is not because of the different colors. It is instead because the cold water is denser than the hot water. So, when the blue-colored cold water jar was at the top, the hot water from below rises upwards. However, the cold water sinks leaving the water of both the jars mixed evenly. During the second time, when the red colored hot water jar was at the top, the result was completely different! As hot water is less dense, it remains at the top, and as the cold water is denser, it stays at the bottom.

Interested in more density science activities? Check out..

Make Sugar Density Rainbow

Create Fireworks in a Jar / Shaving Cream Rain Clouds

DIY Lava Lamp

Now, do you know why hot water is less dense than cold water?

Well, When you heat water, it becomes hot. As a result, its molecules start to move at a faster pace. They move farther apart from each other resulting in more space between each of them. In short, when water is heated, the molecular motion increases, and the intermolecular space increases. When there is more space than cold water of the same volume, the weight becomes less because of the presence of a fewer number of molecules. This does not happen when water is cold. So, hot water is less dense than the same volume of cold water.

Now, you may be wondering that if this is the case,  why ice is less dense than water?

We all know that ice cubes float in a glass of water. Isn’t it? Well, it is because water has an unusual and rare property.  When water becomes ice, its molecules form a crystalline structure and are pushed apart from each other. This implies that the molecules of ice are not as close as they are in liquid water. In brief, the intermolecular space in ice is more than that of the liquid water, and this makes it less dense than water.

This amazing video of the hot and cold water experiment gives a deep insight into density and the way the hot water and cold water behave because of the difference in densities.  You can also try to do a six-second experiment in which all that you need to do is to quickly pour a glass of orange-colored hot water and blue-colored cold water of equal volume in a container at the same time. You will notice that while the blue-colored cold water quickly sank at the bottom, the orange-colored hot water rises up to be distinctly at the top!

Isn’t the experiment too simple to understand why do hot water rises and cold water sink? So, learn while having loads of fun!

•   http://www.learnz.org.nz/argofloats142/bg-standard-f/properties-of-the-sea%3A-salinity-and-temperature
• https://www.exploratorium.edu/science_explorer/watertrick.html#:~:text=So%20hot%20water%20is%20less,hot%20water%20is%20on%20top%3F
• https://vine.co/v/M5YiLngnLjK
• https://socratic.org/questions/54bfd865581e2a7c49ba18c2
• Image Credit : https://www.youtube.com/watch?v=QFZiKtLFZes

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Hot and Cold Water Density Experiment

July 20, 2022 By Emma Vanstone Leave a Comment

This easy science activity demonstrates the difference in density between hot and cold water. It can be a bit messy so I would either do it outside or put the jars in a tray.

The demonstration works as cold water is more dense than hot water so the hot water sits on top of the cold.

When water is heated, water molecules move around faster, bounce off each other and move further apart. As there’s more space between the water molecules the density of warmer water is less than the same volume of cooler water.

You’ll need

Two small or medium glass jars

Small sheet of card

Food colouring

Tray – optional but advised

How to make hot and cold water density jars

Fill one of the jars with hot water and add a couple of drops of red food colouring.

Fill the second jar with cold water and add a drop of blue food colouring.

Check both jars are as full as possible.

Hot water on top of cold

Place a sheet of card over the jar filled with hot water and carefully place it on top of the jar with the cold water.

When the jars are balanced, carefully remove the card.

The two colours of water should remain separate.

Cold water on top of hot

Refill the jars and try again. This time place the cold water on top of the hot water.

The two colours of water should mix.

Density of water

Warm water is less dense than cold water so the red warm water sits on top of the cold water when the card is removed from between the jars.

If you put the hot water on the bottom the colours mix as the denser cold water drops down into the less dense hot water.

Our photo isn’t perfect as it’s hard to remove the card between the jars without some water spilling out, but do send me a photo if you get a better result.

Another density demonstration can be done using salt to increase the density of one jar of water. In the image below the blue water has the salt added.

Safety Notice

Science Sparks ( Wild Sparks Enterprises Ltd ) are not liable for the actions of activity of any person who uses the information in this resource or in any of the suggested further resources. Science Sparks assume no liability with regard to injuries or damage to property that may occur as a result of using the information and carrying out the practical activities contained in this resource or in any of the suggested further resources.

These activities are designed to be carried out by children working with a parent, guardian or other appropriate adult. The adult involved is fully responsible for ensuring that the activities are carried out safely.

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Hot and Cold Water Density Experiment

What happens when hot and cold water meet? This easy and colorful hot and cold water science experiment reveals how temperature affects the density of water, giving kids a fun way to see science in action!

In this experiment, we explore the concept of density by comparing how hot and cold water behave when mixed.

Density measures how tightly packed molecules are in a substance. Observe how the density of water changes with temperature, using vibrant colors! Let’s explore how cold water molecules and hot water molecules interact in this fun science experiment .

Grade Level Recommendation : 3rd Grade and above.

💡Find printable instructions and an observation sheet for this experiment in the CLUB .

• 2 clear glass jars or cups (baby food jars work well)
• Food coloring (red and blue work best)
• Warm (not boiling)
• 2 index cards or pieces of stiff paper

Hot vs Cold Water Mixing Instructions

Ask: Is cold water denser than hot water? (leading to cold water sinking and hot water rising)

Prepare the Water : Fill one jar with cold water and add a few drops of blue food coloring. Fill the second jar with warm water and add a few drops of red food coloring.

💡 For this science experiment, it’s important to have the same volume or cold water and the same volume of hot water. Learn more about variables here .

Invert the Hot Water Jar : Place an index card on top of the hot water jar, ensuring it’s tightly sealed with no gaps.

Stack the Jars : Carefully invert the hot water jar and place it on top of the cold water jar.

Remove the Card : Slowly pull out the index card so the jars are directly connected.

Hot and Cold Water Density Experiment Explanation

In this experiment you would have noticed that the red hot water stays on top of the cold blue water because hot water is less dense than cold water. When reversed (cold water on top), the colors mix quickly to make purple water as the denser cold water sinks. This is because hot water rises and cold water sinks!

Density is a property that explains how tightly molecules are packed in a substance. In cold water, the water molecules are closer together, making them denser. When water is heated, the water molecules move apart and bounce around, decreasing their density. There are fewer molecules in hot water and it weighs a bit less than the same volume of cold water.

In this experiment, the warmer (less dense) water stays on top of the colder (denser) water. However, the denser cold water sinks if you put cold water on top of hot water, causing the two to mix rapidly. This experiment demonstrates how the temperature of a substance can affect its movement and interactions.

This is also why ocean currents and weather patterns occur—cold, dense water sinks while warmer water rises!

💡 Try our Ocean Current Activity to demonstrate this.

Extension Activities:

• Temperature in Nature : Research how temperature changes from day to night.
• Salt and Water Density : Add salt to the cold water to see if it becomes denser.
• States of Matter: Explore experiments that involve matter and its properties, including how changes in temperature affect substances.

Related Experiments To Explore Density

Here are some fun density experiments :

• Oil and Water Science : Try activities that show how oil and water don’t mix because of their different densities.
• Lava Lamp Science Experiment : Discover how density and temperature changes cause bubbles to rise and fall, just like a lava lamp!
• Liquid Density Tower: Layer or mix different liquids to observe how liquids with different densities either float or sink.

Helpful Science Resources

Here are a few resources that will help you introduce science more effectively to your kids or students and feel confident presenting materials. You’ll find helpful free printables throughout.

• Best Science Practices (as it relates to the scientific method)
• Science Vocabulary
• All About Scientists
• Free Science Worksheets
• DIY Science Kits
• Science Tools for Kids
• Scientific Method for Kids
• Citizen Science Guide
• Join us in the Club
• Printable Science Project Pack 👇

Subscribe to receive a free 5-Day STEM Challenge Guide

~ projects to try now ~.

Screen-Free STEM Activities for Kids and Children's Books - myworldtheirway.com

Hot and Cold Water Science EXPERIMENT

Are you looking for a science experiment to do with your kids at home? Then, wow your preschoolers or kindergarteners with a science experiment that teaches them how the density of water changes when it is heated. After all, who doesn’t enjoy science activities for kindergarten that only require common household items?

SUPPLIES FOR THE WATER SCIENCE EXPERIMENT

You will need an adult to supervise this activity as it involves hot water.

• Two identical wide mouthed small clear glass jars
• Food Coloring – Red and Blue
• Index or plastic card ( Old playing card can be used if it covers the mouth of the jar )
• Shallow Dish/Plate or baking pan
• Hot and Cold Water

How do you do hot and cold water density experiment?

Fill one jar with cold water and the other with hot water.

Pour blue food coloring into the cold water and red food coloring into the hot water.

Make sure both jars are completely filled with water. To avoid spills, place them in the shallow plate.

Tap the card gently on top of the hot water jar. The card should completely cover the jar’s mouth. It will aid in the formation of a seal between the water and the jar.

Pick up the hot water jar with care (you’ll need an adult for this part) and turn it completely upside-down.

If the jar is tilted but not completely turned over, the water will gush out and make a mess. So, without hesitation, flip the jar over.

You may not need to place your hand on the card because the vacuum created inside the jar keeps it on the surface.

Before attempting it with hot water, it is best to practice turning the jar upside down with an index card placed on top of it under the sink using tap water.

Place the red jar upside down on top of the blue jar. Check that the edges of both jars are perfectly aligned all around.

Allow someone to hold both jars while you slowly and patiently pull out the card from between the jars.

RELATED POST : HOW DOES WATER WORK AS A MAGNIFYING GLASS

DENSITY EXPERIMENT : THE SCIENCE OF Hot and Cold Water

Why does hot and cold water not mix?

Empty and clean both jars. Carry out the previous experiment, but this time turn the blue jar upside down and place it on top of the red jar. What happens next? Why does the water mix this time?

The reason for this is that when two liquids of different densities are combined, the liquid with lower density floats on top of the denser liquid.

Hot water has a lower density than cold water.

When water is heated, the water molecules begin to bounce off each other, causing them to move farther apart and thus create more space between the molecules.

Eventually, a volume of hot water contains fewer molecules and weighs less than a volume of cold water.

As a result, hot water is less dense than cold water.

RELATED POST : WHAT IS WATER COHESION AND WHY IS IT IMPORTANT

When you place the jar containing hot water on top of the jar containing cold water, the cold water does not have to rise because it is denser than the hot water and thus remains at the bottom.

When you place the jar with cold water on top of the jar with hot water, the hot water rises to the top because it is less dense, mixing with the cold water along the way and creating purple water.

FURTHER EXTENSION ON Water Density

Try the same experiment with a jar of salted water and a jar of plain water. And let us know in the comments section which one is more dense.

Check out some of these great books on science experiments that are simple and fun to do at home if you want to stir up your children’s scientific curiosity.

(Disclosure : Some of the links below are affiliate links, meaning, at no additional cost to you, I will earn a commission if you click through and make a purchase)

Thanks for reading! We hope you enjoyed this post on hot and cold water science experiments. Be sure to check out our other posts for more fun and interesting STEM activities you can do at home with your kids. As always, if you have any questions or comments, feel free to leave them below. Happy experimenting!

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February 14, 2021 at 2:30 pm

Oh love a bit of easy STEM! maybe this is a good one for half term, if I have jars….

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The immiscibility of hot and cold water

The density of hot and cold water.

Does water always mix with water? You might be tempted to answer yes. But the truth is that specific parameters such as temperature and gravity can prevent two solutions of the exact nature from mixing. With this experiment, you’ll understand everything!

You will need:

• Two water glasses
• Food coloring
• A rigid plastic plate
• Otherwise: a Ziploc bag and rigid cardboard of 10 cm x 10 cm

From 6 years

Difficulty : easy

This experience requires the help of an adult

Let's experiment.

Fill a glass with tap water, add a few drops of food coloring and place it in the refrigerator overnight.

The next day, fill the second glass to the brim with hot water and add a few drops of food coloring. Place your two glasses in a dish

Place your piece of hard plastic on top of the hot water glass and gently turn it over to balance it on top of the cold water glass. The air pressure in the room should keep the plastic stuck to the glass.

With the help of an adult, carefully remove the rigid plastic at the interface and observe what happens. Do the colors mix?

This step requires a lot of agility. Also, try again if you don’t get it right the first time.

Now you will repeat the experiment and place the glass of cold water over the glass of hot water. What do you observe?

Understand the experiment

Observations.

Amusingly, you find that the colored liquids do not mix when the glass of hot water is placed on top. However, the colors mix when you use tempered water in each glass or place the cold water glass on top. Can you guess what’s happening?

Hot and cold water have different densities.

The water mixes with water, right? And yet, you notice that the colors stay on their side. Does the temperature have anything to do with it? Yes, the temperature changes the density of the water. In cold water, the water molecules are closer together. Coldwater is, therefore, denser. That means that cold water weighs more than hot water. The water molecules in hot water are further apart. So hot water is less dense than cold water. For the same volume of liquid, hot water will be lighter.

If you put the glass of hot water on top of the glass of cold water, the colors do not mix. You even get the impression that the yellow color is floating on top of the blue. When you remove the plastic, the two solutions don’t mix because the heavier cold water stays at the bottom. In contrast, the lighter hot water stays on top.

When gravity gets involved.

Suppose you invert the glasses to put the cold water solution on top, the solutions mix. That makes sense because the forces of gravity will pull down the heavier cold water. It sinks, causing the colors to mix in its path. That’s why you get green.

Why do icebergs float?

If cold water is heavier, why doesn’t ice sink? And yet, ice cubes, ice floes, and icebergs float.

In the solid-state, atoms and molecules are closer together. Solids are, therefore, denser than liquids, except in the case of ice. As water molecules form, they leave larger spaces to form crystals. This decrease in density makes them lighter.

Moreover, icebergs are formed with fresh water from glaciers. But the polar seas are salty, therefore, denser. It is for all these reasons that icebergs float instead of sinking.

Did you know?

The variations of warm and cold water in the seas and oceans form powerful ocean currents circulating on the bottom and surface of the oceans. These ocean currents help redistribute the heat stored in the oceans around the world and regulate the climate.

You can try the same experiment, but this time using salt. Saltwater is heavier than pure water. By adjusting the salinity of the water, you can reproduce the density stages in a vertical container.

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Did you know that plastic can also be produced from natural resources? The best example is milk! Milk proteins, huge molecules like those in plastics, can, under certain conditions, agglomerate to form a solid. […]

Prepare an orange caviar

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Navigating By Joy

Learning, laughing and loving together, the amazing water trick – investigating density.

This fun science trick demonstrates that hot and cold water have different densities.

The demonstration reminded my kids that lower density liquids float above higher density liquids. They learned that hot water molecules move faster and further apart from each other than cold water molecules.

The trick also allowed us to revisit the topic of surface tension and to build on the  air pressure science  we learned last term.

What you need

• 2 identical jars or drinking glasses (eg babyfood or salsa jars)
• hot and cold water
• red and blue food colouring
• index cards or similar
• a large shallow dish to catch spills

What you do

1. Cut a square of card big enough to completely cover the mouth of a jar.

2. Fill one jar with cold water. Add a drop of blue colouring and stand the jar in the baking pan.

2. Fill the second jar with very hot water. Add a drop of red colouring.

3. Slowly add more hot water to the red jar until you see a bulge of water over the rim. (Take the opportunity to talk about surface tension here.)

4.  Lay the square of card on top of the jar of hot water and tap it gently.

5. Ask your students to predict what will happen when you quickly turn the jar upside down. Then invert the jar, and discuss how air pressure and surface tension keep the card in place and the water in the jar.

6. Put the upside-down red jar on top of the blue jar.  Ask your students to predict what will happen when you slowly pull out the card, then do so.

What happens

When you remove the card between the two jars, the hot red water stays in its jar on top and the cold blue water stays on the bottom.

Reverse the jars

7. Repeat the experiment the other way round. Turn the jar of cold water upside-down and put it on top of the hot water jar. Again, ask students to predict what will happen when you remove the card.

When you remove the card, the water quickly turns purple, as the cold and hot water mix together.

The scientific explanation

When water is heated, the water molecules move faster. They bounce off one another and move further apart. The extra space between the molecules means the same volume of water weights slightly less and is less dense than cold water.

When we put the hot water on top , the less dense hot water floats on top of the denser cold water. The red water and blue water stay in their respective jars and do not mix.

When we put the cold jar on top , the more dense cold water immediately sinks to the bottom and the two colours mix.

We talked about a previous demonstration in which we created a column of liquids with different densities, and reminded ourselves by pouring water into a glass of oil and watching the oil float to the surface.

More fun water experiments

The Tiger Chronicle  recently did a bunch of  fun water experiments . I especially like the supercooled water video.

All Things Beautiful explored density  as part of their  science investigations that all students should do before high school  series.

I found the Amazing Water Trick at Exploratorium .

I’m appreciatively linking up here:

Science Sunday

Science Ideas From After School Link Up

Wonderful Wednesdays

The Hip Homeschool Hop

Entertaining and Educational

Weekly Wrap-Up

Collage Friday

41 thoughts on “ The Amazing Water Trick – Investigating Density ”

That’s a cool experiment and it does go well with the oil/water/layer density experiment.

Thanks Julie. Yes it’s nice when things link up and learning is consolidated, isn’t it?

That is a great way to show density! I love it!!

Thanks Phyllis!

We tried this years ago, but I’m afraid we didn’t get such wonderful results as you. I remember lots of wet going everywhere! Maybe it’s time to try again. I really do have to pull up my science socks and get sciencing again this year! (spell check does not like me!)

I was surprised it worked as well as it did! Sciencing should definitely be a verb. 😉

Love how you conceptually linked the experiments here to work you had done in the past! And C(9)’s expression as she watches the water molecules migrate is priceless! Will have to do some water experiments soon with the kids–they look like such fun!

Both children look a bit perplexed at what’s going on, don’t they?! I’ll take it as a sign the demo made them think! 🙂

This is a very cool experiment. I’ll have to give it a try. Fingers-crossed for good results — we aren’t always successful with our science experiments…. 🙂

Some unsuccessful experiments is probably a sign you’re doing a good amount of science, Hwee! Sometimes we learn the most from the ones that don’t work.

This is such a great experiment/demonstration to do with kids. I’ll have to put it on our list of things to try. I’m so glad you shared at the After School Link Up.

I liked it because it’s simple but demonstrates a number of science concepts – good value! 😉 Thank you for hosting the After School Link Up – I’m very happy to have found you!

Great ideas! I love the hot and cold water experiment – that’s really cool!

Thanks Tonia!

I really like this demo. We did a similar experiment making an underwater “volcano” by placing colored hot water in a flask then down into a tank of cold water. I like the smaller scale of this one and the addition of the paper. Nice job documenting the process, too.

Thank you, Carol. I love the sound of the underwater volcano – what a great idea! Did you post about it? I will have a look on your blog.

Fabulous! Love! 🙂

Thanks, Carol! We did too. 🙂

Love it and pinning to my science board. It looks almost like magic 🙂

It does, doesn’t it, Natalie? And magic always goes down well round here! 🙂

Coolness! (or hotness, depending on your view!). I also like the hot and cold water balloon demo (I put a drop or two of blue and red colouring in for extra special effect): http://www.abc.net.au/science/experimentals/experiments/episode17_1.htm

Ooh yes – thanks Ingi, that one look fun too! I’ve put it in the queue!

Popping in from the Weekly Wrap-Up!! This looks so cool. I think my kids will definitely want to try this.

Have fun with it, Shelly!

Ok this is just way cool! We are trying this next week!! I always love your Science posts Lucinda. You always have the most fun with your kids!

Thank you so much, Karen!

Thanks Mary!

Lucinda, this is cool that you could do this with just water and food coloring. I learned something new today 🙂

Isn’t homeschooling great for playing and learning alongside our children? 🙂

How neat! We’ve done the column of liquids but never tried this with hot and cold. 🙂

Thanks, Leah! I’d never seen it before, either.

This is such a cool experiment. I’m so glad you shared it a the After School Linky Party. I’m pinning this for future use with my son!!

Thank you. (And I’m glad you stopped by so I could find your blog!) Enjoy the “magic” water experiment!

I’m featuring this tomorrow on my blog at the After School Linky. Stop by, check out the feature, and share more! I’ve also pinned it to the After School pinterest board.

Thank you so much for the feature – I love your linky. Very happy to have discovered it!

This brought back memories from science class, long ago! I loved seeing the results of layering liquids with different densities. What an interesting and fun thing for kids to explore.

Thanks, Bella. Your science classes sound like they were more fun than mine! Or perhaps you just have a better memory. 😉 We like pretty, visual science round here!

This is a great post! I’m featuring it as part of a round up of science activities today.

Thank you so much, Anna!

Thanks for hosting. I can't wait to check out some of the other blogs. Everything looks yummy. I'm new to your link party and would love it if you stopped by my blog. http://www.michellestastycreations.blogspot.com . Thanks, Michelle

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Forgetful Momma

Secular Homeschooling

Temperature and Water Density Science Experiment

Science experiment fun is the best, fun way to learn. And a fun activity to do outside in the beautiful spring weather. The perfect thing to do this time of year is to spend time outside. This temperature and water density science experiment is the perfect experiment to take outside.

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When you are stuck home and bored , you do science experiments that you have always wanted to try but always figured would be a huge mess. But again, boring means just doing it no matter what.

This science experiment is easy to do but does pose the risk of making a mess. Embrace it, or go outside where you won’t worry about the mess.

What you need:

• two Mason jars

What you need to do:

• Fill one jar with cold water and add food color.
• Fill the other jar with the hottest water you can while still being able to touch the jar. Add a different color of food coloring to the water.
• Place the index card over the opening of the color water jar.
• While holding the index card in place flip the jar over and on top of the jar of hot water.
• Quickly remove the index card and watch what happens.
• Redo the experiment but instead placing the jar of hot water on top.

Scroll down to find a printable version of the directions.

How to Do this Temperature and Water Density Experiment

I had a towel under the jars because I was prepared to make a huge mess. I was fully expecting the whole jar of cold green water to pour everywhere. BUT I was surprised with only a few drops of water being spilled.

Thanks to my school supply stash , I had everything for this science experiment including the index cards. I placed an index card on the top of the jar of cold water, holding it in place, I quickly flipped it over onto the top of the jar of warm water and pulled the index card out from between two.

You will see the warm water on the bottom quickly rise and mix into the cold water. The cold water jar on the bottom barely mixes with the warm water on top.

Science Experiment E-Book

What’s Happening

The molecules in hot water move faster than those in cold water . Hot water molecules bounce around and leave gaps. This makes hot water slightly less dense than cold water.

Cold water on the bottom, the denser cold water stays there.

Cold water on the top, heat molecules rise. 

Water Density

• two mason jars

Instructions

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