Density Science for Kids : Create Fireworks in Water & Oil

We decided to make fireworks at home. Did you hear it right? Yes, you did. At home DIY explosives. But do not panic as they are as safe to make and can be played by little ones. In addition, you could teach density science to kids.

Does that sound exciting?

We decided to make two difference density science experiments to teach my daughters. Believe me, you will become a kid when you see the results. You will start loving to do this quite often. We did not buy any expensive things but used only the items available at home. The best part – you can do both these experiments in less than ten minutes.

Let’s start with the first one.

Shaving Cream, Water and Food Coloring Experiment

Clouds are always sound interesting and mysterious too for kids especially pre-schoolers. Today let’s clear the question marks on our kid’s faces when they see clouds and rain with our density science experiment.

learn how rain clouds form Go science girls

This is a super fun and simple experiment to explain kids about the clouds formation and rain. Just fascinate our kids by bringing clouds and rain to our home since we cannot bring the real clouds though. Do not worry about the things we need to do this experiment. It sounds complex but it is very easy to do using a few commonly found ingredients in our home.

My children are eagerly waiting to watch the experiment instead of listening about it to be frank!! 🙂 Let’s begin our activity on density.

What all you need to create shaving cream rain clouds?

[*Product links are affiliate links. Your support is highly appreciated]Things We Need Go Science Girls

Instructions on How to create fireworks 

Step-1 :  Begin this activity by simply asking your child to fill the glass container we have taken. Make sure not to fill it completely and ask to leave some space (about an inch from the rim).

pour water to the glass Go Science Girls

Step-2 : Now the exciting part to the kids is adding shaving cream 🙂 .  But,  kids need to be very careful while adding shaving cream on top of the water filled glass cup. Make sure not to add more shaving cream or do not make it thick since it takes very long time for the rain to fall. Also, waiting is the boring thing for kids while doing the experiment. So, do not make it too high.

Here, the water in the glass cup represents atmosphere and the shaving cream is the cloud.

Add shaving foam Go Science Girls

Step-3 : Ask your kid to drop few drops of food colour to the foam already added to the water in the glass cup. Here, you can use a syringe or eye dropper to drop the food colour closer to the edge of the glass cup so that it falls quickly.

Add colour on the foam

Step-4 : Here comes the most awaited step to our kids. My two little girls made their eyes big to watch the effect it is going to give 🙂

We need to wait for few minutes to see such a beautiful and exciting rain like effect because it depends on the size and thickness of the cloud.

learn rain clouds form

Ask your kids to observe carefully!! The weight of the food colour or dye slowly starts to push the foam or cloud and falls down through the water creating a pretty and cool rain like effect. It doesn’t resemble the droplets like real rain but it gives something more like streaks of rain falling. BeautifulJ

At this point, you can take advantage and start discussion with your kids on colours and colour mixing. This helps to develop motor skills in your kids.

Tisha and Pritika loved trying this experiment with different colours and glass cups. They enjoyed watching streams of different food colouring fall like droplets through the foam and then swirl around the water. They also have some great questions but found it lovely experience. J

Science is always exciting, wonderful and fun for curious children and my children are not less to fall under that category to keep on trying different, simple and easy science experiments. That doubled my energy to explain them the same concept using different ingredients found in our home. This helps our children to become good at thinking and observing.

Science experiment for kids

Science Behind Shaving Cream Rain Clouds

Encourage your kids to ask questions and discuss with them about the experiment. The following questions might help.

How do you make rain clouds with shaving cream?

Fill the glass cup (about three quarters full) with water. Use generous amount of the shaving foam to create a cloud on top of the water. Let the foam settle a bit. Now drop food colouring into the ‘cloud’.  As your cloud fills up, the food colouring drops will fall down into the water creating a streak of colours giving rain-like effect.

How do you make a cloud in a jar?

You can use the shaving cream or foam to create clouds in the glass jar. Just pump the right amount of shaving cream on top of the water in a glass jar.

What makes rain fall?

You can tell your kids that the water is like the air, and the shaving cream represents the clouds. As soon as the clouds get saturated with water, they produce rainfall.

What does the water inside the jar represent?

Water inside the jar represents the air or atmosphere.

What does the flowing food color in the jar represent?

The flowing food colour in the jar represents the streaks of colours giving rain like effect.

Do Fireworks cause rain?

Yes, fireworks could change the weather and make it rain. As the fireworks explode, they produce smoke in the air containing high amounts of sulphur and dioxin. Large concentrations of sulphur and dioxin are thought to cause rain.

Why do clouds stick together?

Clouds are  tiny droplets of water that have condensed from water vapor in areas where the conditions (temperature, air pressure and humidity) are exactly right. As the water vapor rises up in the sky, the air gets cooler. The cooler air causes the water droplets to start to stick to things like bits of dust, ice or sea salt. This is how the clouds stay together.

The main motto that encouraged me to do another experiment is “my younger daughter asked me, Mamma! Can you make it happen differently?” So, I decided to make them understand clearly in a different way using different ingredients. Let us get started without late.

Oil, Water and Food Coloring Experiment for Kids

This is not only a hands-on experiment but it would also be a thoughtful science lesson for your kids.

oil and water experiment Go Science Girls

Materials we need

We only require a few ingredients to set up the density science experiment to learn more about density of various substances.

  • Oil
  • Water
  • Food Colour
  • Plastic cups
  • Glass cups
  • Napkin
  • Fork

Things We Need Go Science Girls

Procedure to follow

This activity is also pretty good to watch for kids. It teaches them more about the density concept and creates a ‘WOW’ factor for them.

Step 1

Start by pouring a little amount of oil into a plastic cup until it reaches to one inch length from the bottom line of the cup. Then ask your kid to add a few drops of food colour (any colour of your choice) to the oil in the plastic cup. Mix it nicely using a fork.

Add food colour to oil Go Science Girls

Step 2

Now ask again to fill the glass cup with water leaving some space (around one inch) from the top edge of the glass cup.

Add colour added  oil  in to the water

Step 3

Let your kid to add the oil and food colour mixture to the water in glass cup. At this point, ask the children to observe carefully “what’s happening when we add oil mixture to the water?”

Oil and water does not mix up and the food colour drops gradually falls into the water pushing through the oil layer. Here, explain the kids clearly about ‘how density takes its role to push the food colour drops into the water?’

The amazing part for the kids is that a few minutes later after adding the food colour drops and oil mixture to the water, the food colour drops starts pushing into the water and forming a same gorgeous rain like effect like we observe in the above experiment. Great, isn’t it!? 🙂

My little ones also observed that the water and oil is not mixed up and they both separated forming a layer. You can explain kids the simple science behind this.

In between you can ask your kids to predict the changes that are going to happen during the experiment. You can also ask them to record the changes by drawing on a paper like what they see and observe while performing experiment.

Yes, I hope you all also agree that this is another such a beautiful experiment to explain density concept to the kids. I really encourage you all to try the above explained two experiments with your own children. Hope it’s going to be a great visual demonstration for you all too!! 🙂

However, just a note that we got struck several times as we did it quickly to understand that it went down before the fun began. Also, food color was more and hence it descended quickly. Finally, we got the trick of adding the solution slowly and allowed it to float on the top. The food color was suspending on the top of the oil.

Let the kids watch, observe and have fun the way ‘firework’ works!!!

Lets Kids Learn Density

Science Facts Behind The Fireworks

Density is the science behind this activity. It is the measure of the weight or mass of an item by measuring the space it occupies (volume).

Water does not mix with oil as the molecules in the water get attracted within and not with oil molecules. Also, oil is not as dense as water thus causing oil float on the top and makes two individual layers.

Food colors are another watery substance and hence do not mix up with oil in spite of stirring well.  But you can see the food color becoming small droplets and temporarily float in the oil. Again it is dense when compared to the oil and later on, slowly fall into the water.

Here is some Q&A section that can help with your discussion.

What happens when you add oil to water and food coloring?

The molecules of water do not mix with the molecules of oil when you add oil to water. Even if you try to shake up the liquids, the oil breaks up into small little drops, but they still separate. Also, food coloring only mixes with water and never mix with the oil. When you add the water into the bottle of oil, the water sinks to the bottom and the oil floats to the top. Oil floats on the surface because water is heavier than oil. Scientists say that the water is more dense than the oil.

Will food coloring mix with oil and water?

Since the food color is water-based, it will only dissolve in the water but not in the oil. It remains as small droplets when food colour is mixed with the oil.

Why does food coloring mix with water and not oil?

Food Colour is a water-based drop which is more dense than oil. when the right gravity forces are formed the food colour falls down into the lower layer of the water.

Does food coloring dissolve in oil?

No, food colour do not like to mix with the molecules of oil.

How do you color oil with food coloring?

Many food coloring sources are water-based, which will not mix well with any kind of oil. This means colorless oils must be combined with oil-based food coloring in order to create myriad colors.

How will you separate oil and water from their mixture?

One way is to add some amount of salt to the mixture, which will absorb water from oil by which the white crystals will turn blue, meaning that the salt has absorbed water. The salt will not dissolve in oil.

How long does it take for water and oil to separate?

It takes time for the oil to separate from water. Depending on the difference in density between oil and water, the temperature, the size of the oil droplets in the mixture and the type of oil, the separation may take from minutes to days.

Few more density science activities:

Sugar Density Rainbow Making

DIY Lava Lamp at Home

Oil and food coloring on top of water

Oil And Water Experiment With Food Colouring

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Density science experiment with shaving cream and water

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