sugar water layer experiment

Get Your ALL ACCESS Shop Pass here →

Rainbow In A Jar: Water Density Experiment

Water science is awesome! This water density experiment  with sugar uses only a few kitchen ingredients but produces an amazing science experiment for kids!    Water experiments for kids make great hands-on learning projects for kids! In this experiment, kids will explore the density of liquids, things that dissolve in water, and color mixing.

Why is Science for Kids so Important?

Kids are curious and always looking to explore, discover, check out, and experiment to discover why things do what they do, move as they move, or change as they change!

Science learning surrounds us, inside and out. Kids love checking things out with magnifying glasses , creating chemical reactions with kitchen ingredients , learning about solids that dissolve in liquids, and exploring stored energy !

Look through all our Simple Kitchen Science Activities for home or school use!

Use the Scientific Method

This rainbow water density experiment is a fantastic opportunity to use the scientific method and record your experiment using the free mini worksheet pack below.

You can read about using the scientific method here , and find more information on the independent and dependent variables used in the density experiment below!

The first step in the scientific method is asking a question and developing a hypothesis.

What do you think will happen when you add one mixture of sugar and water to another? I think the mixtures will___________. This is the first step to diving deeper into science with kiddos and making connections!

Water Density Science Fair Project

You can also easily turn your water density experiment into a fantastic presentation along with your hypothesis. Check out the resources below to get started.

• Easy Science Fair Projects
• Science Project Tips From A Teacher
• Science Fair Board Ideas

What is Water Density?

Density is all about the compactness of stuff in space. For this experiment, the more sugar in each glass of water, the greater the density of the water. Same space, more stuff in it! 

The denser the substance, the more likely it will sink. This is how our rainbow sugar water density tower works! Learn more about density!

Increasing the amount of sugar in the solution but keeping the water constant creates solutions with increasing densities. The more sugar you mix into the same amount of water, the higher the density of the mixture. So, density explains why the colored sugar solutions stack on top of each other inside the baster.

You could vary this water density experiment by looking at the density of different concentrations of salt dissolved in water!

YOU MAY ALSO LIKE: Viscosity Experiment For Kids

How to Make a Rainbow in a Jar

Note: You can also try a similar sugar water density activity with a Skittles rainbow in a jar .

SUPPLIES NEEDED:

• 4 Glasses or cups
• warm water and 1 cup measuring cup
• sugar and measuring teaspoon
• food coloring
• spoon and baster 

INSTRUCTIONS:

Recommended age: I suggest this experiment for upper elementary through middle school and beyond. It is not suitable for younger kids without plenty of adult assistance.

STEP 1:  Set out 6 glasses. Measure 1 cup of water into each glass. This is a great time to explain the importance of all the glasses having the same amount of water! You can read more about the scientific method for kids.

STEP 2: Add a few drops of food coloring to each glass of water. You could have your child mix the colors or help them with mixing the colors!

Note: From experience, we have found that 4 colors are the easiest to work with!

STEP 3.   Measure and add a different amount of sugar to each glass of colored water. We have since cut our experiment down to just 4 colors, but you can experiment with all of them.

• RED COLOR – 2 TBSP
• YELLOW COLOR –  4 TBSP
• GREEN COLOR – 6 TBSP
• BLUE COLOR – 8 TBSP

STEP 4.   Stir until as much of the sugar is dissolved as possible.

STEP 5.   Use your baster or pipette to create a colorful rainbow in a jar.

Tip: Have your child try two colors for an easier version!

• Squeeze the baster and put it in the red water. Release a little of the pressure to suck up some red water.
• Keep the baster squeezed, transfer it to orange, and release more to suck up some orange water.
• Continue to do this for all the colors. Leave enough pressure in the baster to get you through all six colors.

Create a Rainbow Water Density Tower

NOTE: This is probably a better experiment for elementary school or with a very patient kid. My son enjoyed trying to make the tower and simply experimenting with mixing colors.

This rainbow sugar water density tower does take a slow hand and patience.

We used a test tube from our favorite science kit! This time we found starting with the densest water {purple} worked the best.

STEP 1:   Use the baster’s measuring marks to ensure you get the same amount of each color. Add the purple to the tube.

STEP 2:   Next, add the blue, but add the blue very, very slowly. Slowly release the water along the jar’s side or glass.

STEP 3:   Continue to do the same thing,  working your way back through the colors. Slow and steady. We practiced a few times before we got a full rainbow.

You can experiment with different methods and challenge your kids to come up with a plan of action to make a rainbow in a jar.

We kept our artificial rainbow around for a couple of days. It’s so pretty in the light!

More Density Experiments to Try

You could also try a density tower with various liquids or even a homemade lava lamp to learn more about density.

Or how about a floating egg to demonstrate salt water density ?

Check out this oil and water science with a fish theme for a preschool-friendly density activity.

More Science Experiments for Kids

Let’s look at even more awesome everyday science experiments every kid should try!

• Easy to Make Oobleck Recipe
• Fantastic Magic Milk
• Best Ever Naked Egg
• Fun Popsicle Stick Catapult

More Helpful Science Resources

Science vocabulary.

It is never too early to introduce some fantastic science words to kids. Get them started with a printable science vocabulary word list . You will want to incorporate these simple science terms into your next science lesson!

WHAT IS A SCIENTIST

Think like a scientist! Act like a scientist! Scientists like you and me are also curious about the world around them. Learn about the different types of scientists and what they do to increase their understanding of their specific areas of interest. Read What Is A Scientist

SCIENCE BOOKS FOR KIDS

Sometimes the best way to introduce science concepts is through a colorfully illustrated book with characters your kids can relate to! Check out this fantastic list of science books that are teacher approved and get ready to spark curiosity and exploration!

SCIENCE PRACTICES

A new approach to teaching science is called the Best Science Practices. These eight science and engineering practices are less structured and allow for a more free**-**flowing approach to problem-solving and finding answers to questions. These skills are critical to developing future engineers, inventors, and scientists!

Printable Science Projects Pack

If you’re looking to grab all of our printable science projects in one convenient place plus exclusive worksheets and bonuses like a STEAM Project pack, our Science Project Pack is what you need! Over 300+ Pages!

• 90+ classic science activities  with journal pages, supply lists, set up and process, and science information.  NEW! Activity-specific observation pages!
• Best science practices posters  and our original science method process folders for extra alternatives!
• Be a Collector activities pack  introduces kids to the world of making collections through the eyes of a scientist. What will they collect first?
• Know the Words Science vocabulary pack  includes flashcards, crosswords, and word searches that illuminate keywords in the experiments!
• My science journal writing prompts  explore what it means to be a scientist!!
• Bonus STEAM Project Pack:  Art meets science with doable projects!
• Bonus Quick Grab Packs for Biology, Earth Science, Chemistry, and Physics

32 Comments

What a super clever and pretty science experiment!

Hello! I tried this experiment with my students today with little success 🙁 The purple and blue separated perfectly, but when green was introduced, it all mixed together from there on. Any thoughts? I’m so disappointed!! Your’s is PERFECT!!!

i love this website..<3

Thank you. I’ll give this a try at home – and if I am successful I’m sure my students can do it too. 🙂

Hope you have good luck! It might take a bit of practice, but it was fun to experiment.

Practice! We had a few with only a few colors too. You have to go very slowly.

it didnt work yours is perfict

It is a tougher project and you have to be quite slow and patient!

Hello, Iam a science teacher too. Thanks for sharing this experiment with us. But there is a point that ı cannot understand.

To make in a baster, squeeze baster and put in red water. Release a little of the pressure to suck up some water. Keeping it squeezed, transfer to orange, release a little more to suck up some water.

I cant understand these sentences because my english level 🙁 Should I make the test tube oily before pouring the colors? In addition Should I use syringe to take the colored waters in order to pour them? if you can explain i will be really grateful

I found this worked well when I added 4 drops of food colouring per glass rather than 2 drop per glass which I tried first. Try adding milk after, the result is really interesting!

Ours did not work at all. Huge flop even though we followed the directions explicitly. Very frustrating. Super messy. Unsuccessful.

The key is to make sure your sugar ratios are all different so they layers separate and you do need to be slow and patient adding in the layers.

We put a cup of sugar in the purple, half a cup in the blue, quarter cup for green, two tablespoons for yellow, one for orange and none for red. Slowly dribbling each color down the side of the test tube was key to avoid mixing layers.

• Pingback: Best Kindergarten Science Activities - WeAreTeachers

what grade is this experiment for?

You can use it with a mix of ages but I think it’s best for early elementary age kids. You can add our free science journal page to it as well.

So I tried to do the experiment and I found that if you actually add the different amounts of sugar to Gatorade colors it works for better results.

• Pingback: Winter Snow Storm In a Jar Science Activity for Kids

Nice Blog. very easy process to do this experiment.kids also try this at home.

• Pingback: Liquid Density Tower Physics Activity and Experiment for Kids
• Pingback: Rainbow Inspired Activities for Kids - FSPDT
• Pingback: Making Rainbows STEM Activities Spring Science
• Pingback: Spring Science Experiments For Kids
• Pingback: Water Science Activities for Kids STEM
• Pingback: 14 färgglada experiment för barn – Bättre hälsa
• Pingback: The Elite Nanny Guide to a more ethical Christmas | The Elite Nanny Company
• Pingback: Rainbow Science Hands-on Activities for Elementary
• Pingback: Best STEM Activities, STEM Challenges and Ideas for Kids All Year!
• Pingback: St Patricks Day STEM and Science Activities for Kids
• Pingback: Apple STEM Activities for Kids | Little Bins for Little Hands

We tried this experiment with 6 colors, a turkey baster and a large glass cylinder. Epic fail. Brown sugar water was our result. We found your instructions, tried again and has great success! We used 4 colors, a pipette and shot glasses and it worked beautifully! Adding the subsequent layers VERY slowly was key. The turkey baster had a tendency to dump too much water at a time. The pipette was easier to control. Thank you!

It is a bit more challenging than most of our activities. Starting with just 2 or 3 colors might help!

Comments are closed.

Subscribe to receive a free 5-Day STEM Challenge Guide

~ projects to try now ~.

Classes for Curious minds

A place for children to learn, experiment, explore and play

For children aged 3-12 years

Sugar Water Density Rainbow Experiment

Learn about density in this fun and simple science experiment.

November 2019

You Will Need

• Food colouring
• Pipette/syringe

The Experiment

• Fill 4 glasses with water. Leave the 5th glass empty.
• Add 2-3 drops of food colouring to each glass of water. Add red colouring to the first glass, yellow to the second, green to the third, and blue to the fourth.
• In the glass with red colouring, do not add any sugar. In the yellow glass, add one tablespoon of sugar. In the green glass add two tablespoons of sugar. In the blue glass add three tablespoons of sugar. Leave the fifth glass empty. Stir the sugar/food colouring/water solution in each glass until the sugar is completely dissolved - you can use warm or room temperature water to speed this up and make sure all sugar is dissolved.
• Using the pipette or syringe, fill the empty 5th glass ¼ full with the blue sugar solution, then add ¼ of the green solution which should sit on top. Then add ¼ of the yellow solution, then ¼ of the red solution to finish. Go slowly, making sure the different layers don’t mix into each other. You should have created a rainbow!

The Science

Density is the number of particles in a given volume. When more sugar is added, more space between the water particles is filled. Adding sugar to the water increases the density of the water, so the more sugar in the solution, the greater the density.

The blue sugar solution has the most sugar so it is the densest as it has the highest number of sugar particles per 100ml of water. The densest solution stays at the bottom, with the least dense on top. The red solution has less sugar so has a lower density, and, as a result, stacks on top of the mixture with a higher density - so the differing densities separate out.

Want More Epic Experiments?

If you enjoyed this experiment and want more fun, more science, and more epic experiments, enrol now in our science ​ enrol now​ in our ​ holiday camps​ and science classes​ where kids can learn, experiment, explore, and play!

Book your Holiday workshops and Term classes today!

Schools & Nurseries

Start a Science or Little Maths club to your school/nursery

We offer tailor-made tutoring to students of Chemistry, Physics, Biology and Maths.

Latest News

We published our first book: FULL OF BRAINS!

Holiday Science Camps

AGES 4-12 YEARS

find out more and enrol

Science Term Classes

AGES 3-4 YEARS AGES 4-7 YEARS AGES 8-12 YEARS

Schools & Nursery Clubs

AGES 3-4 YEARS AGES 4-12 YEARS

Our website uses cookies to give you a better customer experience. By continuing we will assume you are happy with receiving all cookies. ACCEPT You can get more information on cookies HERE

Primary Playground

Rainbow In A Jar Science Experiment

February 25, 2018

I love incorporating easy science experiments into the classroom as often as I can. I thought this rainbow in a jar science experiment was perfect for March.

To make this rainbow in a jar, the students are exploring density by layering sugar water to make a rainbow.

The materials are all things you most likely already have on hand.

THIS ACTIVITY WORKS WELL WITH

Approx. 2 cups of warm tap water

1/2 cup measuring cup

1 Tablespoon measuring spoon

4 small jars of glasses

Approx. 1 1/2 cups of granulated white sugar

Red, blue, yellow, and green food coloring

Tall thin glass or test tube. I used an old Starbucks bottle

4 popsicle sticks

Experiment steps

Measure a 1/2 cup of warm tap water into the 4 jars.

Add 2 drops of food coloring to each of the 4 jars.

To the jar of red water, add 2 tablespoons of sugar. To the jar of yellow, add 4 tablespoons of sugar. In the jar of green water, add 6 tablespoons of sugar. And to the jar of blue water, add 8 tablespoons of sugar.

Stir each of the jars to dissolve the sugar. If your water is not warm enough to dissolve the sugar, put the jar in the microwave for 30 seconds at a time, stirring in between until the sugar is dissolved.

The students can already see at this point that by dissolving increasing amounts of sugar, you’re increasing the density of the sugar water solutions. They can easily see that the jars all started the same and now the blue looks a lot fuller than the red.

Step 5: 

Pour about an inch of the blue water into the bottom of your glass or test tube.

Use your straw to gently drip the green water on top of the blue layer. It works best to place the straw to the side of the glass just above the blue layer. You want to add the layers to the glass slowly and carefully, otherwise, they’ll mix together resulting in a muddled rainbow.

Add the yellow layer next using the same method and last the red layer. Stand back and admire your beautiful rainbow!

I hope your students love making the rainbow and learning about density in a fun way!

If you’re looking for another great science experiment that would be great for the science fair, you might like the simple circuit that we made. You can get all of the details for that project here.

See you next time!

Share this:

July 15, 2019 at 2:35 am

I cannot find regular food coloring any where! Can gel food coloring be used??

July 16, 2019 at 1:56 pm

I’ve never used gel food coloring, but if you can get it to mix with the water it would work just fine. Basically, you are just coloring the water in order to be able to see the layers.

November 9, 2019 at 5:05 pm

What a pretty density experiment!!

April 1, 2020 at 7:34 am

I didnt get layers..All the colours got mixed..what could have gone wrong?

April 1, 2020 at 2:50 pm

Hi there. If you didn’t get layers, the sugar measurements may have been off. Also, the layers/colors need to be added VERY slowly otherwise it will all just become mixed. I hope that helps!

April 2, 2020 at 8:17 pm

Would brown sugar work just as well?

April 3, 2020 at 1:48 pm

My guess would be no since brown sugar contains molasses and would be a different density. But it is a science experiment, so it wouldn’t hurt to try it and see what would happen.

April 9, 2020 at 2:55 pm

So fun! It looks awesome! Takes some time to do though but worth it! Kids thought it was cool but I think I had more fun then they did 😁

May 28, 2020 at 10:12 pm

This was extremely fun. First we did not think it was working but then we put a light from behind and seen the wonderful masterpiece. We tried using a straw and it was a bit hard then we found some droppers and it was a whole lot easier. Thank you.

February 26, 2021 at 8:53 pm

I was wondering about the straw and exactly how that would work. With the droppers, did you have to add the drops really slowly and one at a time? Or could you just squeeze it? Asking, because I want to try this with my two and threes. Some will be able to listen and add slowly l, but some may want to squeeze as hard as they can

February 26, 2021 at 9:41 pm

Hi there. If you’re using a straw, you would plug the top end with your thumb and slowly let the liquid run out of it down the side of the inside of the jar. Same for the dropper. You don’t want to just “drop” the liquid in as it will then mix and you won’t get the density layers. You will just end up with a purple, brown mix. It may work for some of your twos and threes, but it may just be too much for some of them. Maybe an alternative is they watch you do it and then they could play with their own droppers in other colored water and make art on paper.

[…] 7. Brighten a rainy day by making a Rainbow In  A Jar. […]

[…] 7.) Rainbow Science in a Jar […]

[…] Rainbow in a Jar […]

[…] Rainbow in a Jar by Primary Playground […]

[…] Foto: Primary Playground […]

[…] about density when you create a rainbow in a jar with your preschoolers. This science experiment is perfect for spring and […]

[…] different science experiments to do as a class. Some of our favorites are making a rainbow in a jar, making slime, and elephant […]

Leave a Reply Cancel reply

Your email address will not be published. Required fields are marked *

Save my name, email, and website in this browser for the next time I comment.

Notify me of follow-up comments by email.

Notify me of new posts by email.

Latest on Facebook

6 hours ago

Share on Facebook Share on Twitter Share on Linked In Share by Email

8 hours ago

12 hours ago

14 hours ago

16 hours ago

Latest on Instagram

Please go to the Instagram Feed settings page to create a feed.

Sugar Rainbow- Density Science Project

Introduction: Sugar Rainbow- Density Science Project

This is a really very simple yet beautiful experiment that barely requires just sugar/salt and water to do. It works on the principle of density. Let's begin! :)

• 10 spoons of Sugar (Salt can be used instead)
• Equal amount of water in 5 containers
• Food colouring or paint
• A pipette or dropper

Step 1: Take Equal Amount of Water in 5 Containers

take approx. an equal amount of room temperature water.

Step 2: Add a Different Colour to Each Container

Food colouring or paint can be used.

Step 3: Adding Sugar

Add spoons of sugar to the containers in the following order:

• 1st container - 0 spoons
• 2nd container - 1 spoon
• 3rd container - 2 spoons
• 4th container - 3 spoons
• 5th container - 4 spoons

And mix it till all the sugar is dissolved.

Step 4: Take a Glass Jar

Step 5: Order of Filling

the solutions should be filled in decreasing order of sugar. that is,

the colour with 4 spoons of sugar goes first, followed by 3 spoons, 2 spoons, 1 spoon and 0 spoons.

Step 6: Filling the Solutions

You have to fill up each colour one by one using the pipette or dropper very slowly , touching the side of the container (as shown in the picture) .

This is a very important step, if done otherwise, the solutions may mix together

This step requires a lot of patience! But the results are amazing too!

Step 7: The Science Behind It

it works on the principle of density.

The more the amount of sugar in water, the more is the density of water. A more dense liquid is heavier than a less dense liquid because a more dense liquid has more mass per unit volume as compared to a less dense liquid.

So, the water with less density (Less amount of sugar) will float over the water with more density (more amount of sugar) and not mix with it, which creates this beautiful rainbow effect.

Step 8: And Its All Done !

Thank you everyone for your time reading this instructable :)

Participated in the Science Fair Challenge

Recommendations

Art and Sculpture Contest

Outdoor Life Contest

Woodworking Contest

Sugar Rainbow – Stacking Liquids in a Straw

Density differences are revealed in a colorful stack of sugar-water samples.

Print this Experiment

Explore the science of density as you learn how liquids of different densities stack on top each other. A simple combination of some sugar and water with vivid colors leads to an awesome science experience about density.

Experiment Videos

Here's What You'll Need

6 tall, clear glasses (see note in step1.), granulated sugar (you’ll have great results with imperial sugar or dixie crystals.), coloring tablets or food coloring, water (see note in step 3.), clear drinking straw, measuring spoons, small dish or sink, adult supervision, let's try it.

Fill each of the six glasses with water. NOTE: The glasses need to be stable and about as deep as the straw is long. As you fill the straw with solutions, it has to be plunged deeper and deeper into the liquids.

Use coloring tablets or food coloring to dye the water a different, bright color in each glass. Stir it completely.

The first of the six glasses will be just colored water with no sugar. The second color receives one rounded teaspoon of sugar. The third color receives two rounded teaspoons of sugar. The fourth gets three teaspoons and so on to five teaspoons of sugar in the last glass. Stir the solution in each glass until the sugar is completely dissolved. NOTE: Using warm or room temperature water will speed up this process.

Grab the straw and, if you haven’t already, remove the wrapper. Hold the straw near one end, wrapping four fingers around the straw and placing your thumb over the straw’s top opening. To make your Sugar Rainbow, lift your thumb off the opening, dunk the lower end of the straw about 1” (3 cm) into the plain water. Cap the straw firmly with your thumb, lift it out of the water, and dip it quickly into the 1 tsp solution. This time, go a little deeper than you did into the first glass. You want the layers to be about the same thickness. With the straw in the liquid, lift your thumb but quickly replace it. Lift the straw and you’ll have the first and second colored solutions in a stack inside the straw. Continue the dipping process until you have all six colored solutions inside the straw.

It’s a density column of sugar water, a Sugar Rainbow!

When you’re ready, hold the straw over the dish and lift your thumb to empty the straw. Rinse it and make another one.

How Does It Work

Density is the measurement of how much “stuff” is packed into a measured space. That’s how we get the equation for density: Density = Mass (the stuff) ÷ Volume (a measured space). Nearly every substance and material imaginable has a different density. This is especially true for the six solutions you made using sugar and water.

By increasing the amount of sugar in the solution but keeping the amount of water constant, you create solutions that have increasing densities. The more sugar that’s mixed into a measured amount of water, the higher the density of the mixture. As the Sugar Rainbow reveals, a solution with a low density stacks on top of a mixture with a high density.

So, density explains why the solutions stack on top of each other inside the straw, but what keeps the solutions in the straw? You could expect them to just pour out of the straw as you lift the straw from a solution. However, thanks to cohesion (similar molecules attracting each other) and adhesion (different molecules attracting each other), there is surface tension sealing the water at the bottom of the straw. The surface tension is strong enough to help hold the solutions in the straw… as long as air pressure inside the straw is lower than the air pressure outside the straw. Gravity tugs the solutions downward which creates a slight vacuum in the empty part of the straw. That lowers the air pressure inside the straw which is why you need your thumb to cap the straw. This prevents air pressure from equalizing inside the straw. Remove your thumb, air pressure equalizes, and gravity simply moves the colored solutions out.

Take It Further

Use a turkey baster as a replacement for the straw to slowly layer the colored sugar solutions into a larger glass to create an even bigger rainbow. Hold the tip of the baster against the side of the container close to the surface of the liquid already in the glass. Squeeze the baster gently so the water flows slowly down the side of the container and then onto the previous layer. If you try to rush it, the layers will just mix together. Rinse the baster between each layer. Move the baster upward on the side of the glass as needed so it doesn’t touch the surface of the solution. Layer all the sugar solutions in the same way. This can be hard to do but it’s worth the effort when you finish. Get some pictures!

A dramatic salt water density change can be experienced in real life. While humans will (sort of) float in an ocean, they really float in bodies of water like Utah’s Great Salt Lake and the Dead Sea in Israel and the West Bank. They are so salty that it’s nearly impossible to sink in them! Just be sure to rinse off really well when you get out.

Related Experiments

Oil and Water

There’s something very important about oil and water that you probably already know: oil doesn’t mix with water! That explains why oil spills on the ocean float on […]

Color Changing Milk

This unforgettable hands-on learning experience is fun and easy—no wonder it’s one of Steve Spangler’s most popular experiments! Learn how to turn this activity into […]

Bubbling Blob - Lava Lamp

Learn how to make a wave bottle using oil, water, and a secret ingredient that makes the whole thing fizz, bubble, and erupt.

Stained Glass Sugar

Sugar has many uses but maybe you didn’t know it can be used to make “glass” – even stained glass. You combine the science of […]

Amazing 9 Layer Density Tower

With this science magic trick, you’ll put a new spin on our famous Seven-Layer Density Column demonstration. First, you’ll discover how to stack seven or […]

Liquid Layers - Salt Water Density Straw

Density can be a difficult scientific property to grasp. With that in mind, we found a way to make the science of density a colorful, […]

Browse more experiments by concept: