Science is fun for kids when learned hands-on with the help of simple science experiments. Lava Lamp Science Experiment for Kids is easy to do, quick to set and definitely tops the list of science activities to do with kids.
Kids love such experiments and end up learning tricky science concepts without much effort. Lava Lamp Experiment is one of the science activities that kids across ages – be it preschooler, kindergartener or older children – love to do! It is a super fun experiment for adults too.
A visual delight – Lava Lamp is soothing and almost magical to witness! But did you know that underneath the bouncing, bubbling bubbles and colorful fluid motion there’s a lot of science at work?
Table of Contents:
How to Make Lava Lamp With Alka Sletzer
DIY Lava Lamp Without Alka Sletzer
A lava lamp will generate a lot of excitement among your kids to learn science and build their keen interest in STEM.
This science activity is straightforward and cheap to set up. So get your kids to tag along and follow the entire process step by step to create your own homemade lava lamp.
How To A Make Homemade Lava Lamp
A lava lamp is a simple and easy science experiment for kids that can be done using few, commonly found ingredients. There are many ways to make a lava lamp at home.
Choose the one that interests you most.
Quick Tip: Before you get on with the experiment, crack a few Funny Science Jokes to get your kid’s attention and full engagement.
DIY Lava Lamp With Alka Sletzer
This is by far the most popular way to do this simple science experiment. This science activity is so easy that even your little preschooler can do it without much help.
DIY Lava Lamp Materials:
● Clear flask or bottle
● Vegetable Oil – Cooking oil or baby oil work as well
● Food coloring – bright colors give the best effect!
● Alka Seltzer tablets – You can find them at a supermarket or local pharmacy store
How to do it:
Step 1: First, fill about ¾ of the flask with vegetable oil or baby oil.
Step 2: Next, add some water to the flask, making sure not to fill the flask. Allow the water and oil to settle. You will observe the oil and water separate into two different layers.
Step 3: Add a few drops of food coloring to the flask.
Step 4: Finally, break the Alka Seltzer tablet into chunks and add it to the flask.
This will kick-start the chemical reaction, the fun part of this science experiment, and give rise to the lava lamp effect inside your flask!
Related: Indulging kids in science activities early on help them build a natural love for science and spark their curiosity. Club this activity with more simple and easy Preschool Science Experiments to hone their inner sense of wonder!
The Science Behind Lava Lamp Science Experiment
There are several science concepts that underlie the spectacular effect a lava lamp creates. You can encourage your kids to think about the following:
Concept 1: Why did the water and oil separate into two layers?
This has to do with a physical property of molecules known as polarity. Polar and non-polar liquids are immiscible, meaning they will not mix.
Liquids with alike polarity mix, while liquids of unlike polarity separate into layers.
A molecule is said to be polar if the positive and negative electrical charges are unevenly distributed.
Some examples of polar liquids are ethanol and hand sanitizer. Petrol and most oils are non-polar liquids.
Water is a polar fluid meaning it has uneven distribution of charge around it. Each water molecule is made of two Hydrogen atoms and one Oxygen atom.
Hydrogen atoms lend water molecules positive charge while the Oxygen atom lends water negative charge.
But what really causes the uneven distribution of charge in water molecules is its bent shape. This shape causes positive charge from Hydrogen atoms to accumulate on one end of the water molecule and negative charge to gather around the other end of the molecule leading to uneven distribution of charge.
Oil, on the other hand, is a non-polar fluid. This difference between the polarity prevents oil and water from mixing together and causing them to separate into two layers.
Concept 2: Why Does The Water Layer Sink To The Bottom?
Density is another physical property of matter. Density is nothing but how tightly (or loosely) things are arranged in a defined space.
Scientifically, Density can be defined as mass per unit volume.
D = Mass/ Volume
That means, material that is dense packs in more matter per unit volume than materials that are less dense.
This makes denser materials heavier per unit volume compared to materials that are less dense.
Different materials have different weights for a given volume. Water is denser than oil, thus heavier. That is the reason it sinks to the bottom of the flask while oil floats above water.
You can demonstrate the density of liquids using a simple experiment. Take two identical flasks and fill one with water, and another with oil.
Get your children to weigh each flask using a scale and record their mass on a piece of paper.
You will observe that water is heavier. Encourage your kids to share their arguments on why water sinks to the bottom and oil floats on top.
Related: Pair this experiment for kids with activities for kids indoors to add fun to learning.
Concept 3: Why Do Bubbles Keep Moving Up And Down?
The following key processes take place:
1. Alka Seltzer and water react to produce carbon dioxide.
2. Carbon Dioxide (CO2) forms the water bubbles.
3. As CO2 is light, the bubbles float to the top and pop at the surface.
4. The popped water bubbles release carbon dioxide and leave behind water droplets.
5. As water is heavier than oil, the water droplets sink and fall back to the bottom.
6. The process continues as a cycle, creating the beautiful, mesmerising lava lamp effect.
Several improvisations can be done to step up your chemistry skills! You can get children to test the speed of chemical reaction under different conditions such as:
Improvisation 1: Warm water vs Ice cold water
Get your kids to compare the number of bubbles created. At higher temperatures, molecules of water and Alka Seltzer move faster and hit each other more often, which is why you would observe a higher reaction rate with warm water.
Improvisation 2: Whole tablets Vs small pieces Vs powder
Teach children that powder forms bubbles at the highest rate because of the higher contact area. You can even talk about the time it takes to dissolve sugar crystals and cubes to explain this concept.
Related: After your kids have enjoyed the bubbling experiment, teach them How To Make Bubbles with this Easy Bubble Solution Recipe.
DIY Lava Lamp Experiment Without Alka Seltzer
To make Lava Lamp without Alka Seltzer, there are a couple of easy alternatives that can be found handy in your pantry.
Baking Soda and Salt are popular and easy alternatives that will recreate the same magic but without the fizzy tablet. These fun ideas can be easily turned into an enjoyable activity for birthdays.
Lava Lamp Experiment With Baking Soda
Baking soda is a good substitute for Alka Seltzer tablets. But you need to make a few changes to the lava lamp science experiment with Alka seltzer.
Instead of water, use vinegar or citric acid (lime/lemon juice).
How to do it:
Step 1: Add 2-3 tablespoons of baking soda
Step 2: Add the oil up to ¾ of the flask
Step 3: Add a few drops of food coloring to the vinegar or lime juice and mix.
Step 4: Using a dropper, gently add the vinegar and food coloring solution into the flask.
Baking soda is a base, and it reacts with acids like vinegar and lime juice to give off bubbling carbon dioxide.
In fact, there are plenty of acids and bases you can find around your home. A brilliant science activity for kids would be to collect some of them and get your children to guess whether they are acids or bases. Some items could be:
● Toothpaste – Base
● Fizzy drinks – Acid
● Soap – Base
● Cleaning powders/ detergents – Base
● Citrus Fruits like Lime, Orange or Lemon – Acid
You can use a litmus paper test to check which category the items collected fall into – Acid or Base.
Related: Kids love fizzing, bubbling reactions. Check out what all you can do with two simple pantry ingredients with Baking Soda and Vinegar Experiments for Kids.
Homemade Lava lamp experiment with Salt
Another alternative to Alka seltzer is Table Salt. Table Salt gives the same effect but works very differently to Alka Seltzer and baking soda.
Here is how to make a lava lamp with Salt:
Step 1: Follow the same steps of the original lava lamp experiment.
Step 2: Simply replace Alka seltzer with 2-3 tablespoons of salt.
You should see the lava lamp erupt. Your kids probably have mixed salt and water before but would have never seen gas bubbles forming. Challenge your kids to reason out how the lava lamp works with table salt.
Quick Tip: Add in some humour to learning with these funny Science Jokes for Kids. They are sure to boost learning as well as the attention span of your kids.
Science Behind Lava Lamp Experiment With Salt
As you add salt to the flask, it sinks to the bottom of the flask, as it is heavier than oil and water. But as the salt drops through the oil, some oil gets trapped in the salt crystals and reaches the bottom.
When the salt gradually dissolves in water, the oil floats back up because of its lower density compared to water.
Glow in the dark Lava Lamp
A glow in the dark lava lamp is a mesmerizing version of the simple lava lamp. For this version, you will need glowing water. Simply replace water with glowing water to obtain this effect.
Glowing water is a unique type of fluid that has the property of bioluminescence. Bioluminescence causes Glowing water to glow in dark light.
After you’ve added the food coloring, switch off the lights in the room before you add the Alka Seltzer tablets to the flask.
DIY Glowing water
There are several drinks relatively easy to find with which you can produce the glowing effect!
The following drinks give off vibrant colors under black light:
● Tonic water – blue
● Drinks with Vitamin B, like energy drinks – bright yellow
● Syrup – golden yellow
● Sprite, Mountain Dew, and other clear drinks
By using some of these drinks instead of water, you too can create your glow-in-the-dark lava lamp at home! Apart from the drinks, you will need a black light source. This is a source that emits Ultraviolet light.
Other than these drinks, you may use glow in the dark pigment to add to regular water and use it for Glow in the Dark Lava Lamp.
Over to You…
Either version, lava lamps are an experiment that many children will flock around. Remember to help kids understand the scientific principles behind the lava lamp to make it a complete learning experience and bring hands-on learning to the table.
All children will love science when presented to them engagingly and enjoyably! Have fun!