Tel: +86-18638065667    E-mail:
  Video     Our Team    FAQ
News center
You are here: Home » News » Science Classroom » Alpha science classroom: The Limewater Carbon Dioxide Test

Alpha science classroom: The Limewater Carbon Dioxide Test

Views: 4     Author: Site Editor     Publish Time: 2022-02-24      Origin: Site

I'm sure that children are no stranger to carbon dioxide, which we produce in the process of breathing, but carbon dioxide is also a major cause of greenhouse gases, one of several compounds that contribute to global climate change! Today, the alpha science classroom will let children understand that carbon dioxide is all around us through The Limewater Carbon Dioxide Test, a children's chemistry experiments that will help children understand carbon dioxide through two chemical reactions, and tongs enjoy the learning plan and fun brought my kid's science experiments.

Alpha Science Classroom: The Limewater Carbon Dioxide Test, Materials needed

Container with lid (a plastic food container will do)

Distilled water

Tap water

Calcium oxide (lime)



¼ cup measuring cup

White vinegar

Small shallow dish (a baby food jar or salad dressing cup works well)

2 clearwater bottles

Modeling clay

2 bendable straws



Toilet paper

Baking soda

Alpha Science Classroom: The Limewater Carbon Dioxide Test, step-by-step tutorial

Step 1: First, children take a container with a lid and add 1 liter of distilled water and 1 teaspoon of calcium oxide. Stir with a spoon.

Step 2: The children leave the solution overnight. This will be your limewater, then fill a small shallow dish with limewater.

Step 3: Children take out the modeling clay and shape it into a ring under the bendable part of the straw.

Step 4: Children add ¼ cup of water and ¼ cup of white vinegar to a water bottle, take 1 square of toilet paper, and lay some baking soda in the middle of the paper. Roll it up and twist the ends of the toilet paper so the baking soda doesn't spill out.

Step 5: Children drop the baking soda from the toilet paper into a water bottle and immediately insert the end of the straw into the bottle, making sure it is submerged in the liquid. Seal the straw around the neck of the water bottle with modeling clay.

Step 6: The children will bend the end of the straw and dip it into the container of lime water. Observe what happens. Record your observations.


Step 7: Children add ¼ cup of lime water to another clear water bottle. Make a second modeling clay stopper around the second bent straw and insert the straw and stopper into the water bottle.

Step 8: Take a deep breath and exhale into the straw to get your breath into the lime water. Be careful not to suck up any of the lime water and record your observations.


Alpha science classroom tells children that when carbon dioxide, CO2, enters limewater, the limewater becomes cloudy. When you exhale into the bottle, the limewater becomes cloudy.

Alpha Science Classroom: Lime Water Carbon Dioxide Test, Scientific Principles

Chemists refer to baking soda as sodium bicarbonate, a compound with the chemical formula NaHCO3. Vinegar is a mixture of acetic acid (CH3COOH) and water (H20). When the two are combined, the following reaction occurs.

NaHCO3 + HC2H3O2 → NaC2H3O2 + H2O + CO2

However, it is known that this happens in two steps.

NaHCO3 + HC2H3O2 → NaC2H3O2 + H2CO3.

... Where carbonic acid is formed and finally

H2CO3 → H2O + CO2.

Alpha science classroom tells children that carbonic acid breaks down into water and carbon dioxide. The carbon dioxide then bubbles up through the straw and into the lime water.

Lime water is made from calcium hydroxide or Ca(OH)2. Lime, named after the mineral rather than the fruit, reacts with the carbon dioxide in the water to form calcium carbonate, which is white and insoluble in water, causing the water to become cloudy.

Similarly, when we exhale, we are expelling carbon dioxide from our bodies, so breathing carbon dioxide into lime water will produce the same reaction, although it may not happen as quickly due to the smaller amount of carbon dioxide in your breath.

It is believed that the children have gained an understanding of the production of carbon dioxide through the amazing children's chemistry experiments. In the future, we hope that with the help of more interesting kid's science experiments activities, children will learn and work hard to find the solution to carbon dioxide and become an environmentalist to save our beautiful earth.

Alpha science toys' Chemistry Experiment Kit World for Kids has prepared many interesting experimental activities specifically for children to help them grow and become the smartest chemistry wizards by deciphering the mysteries of chemistry for them.


Manufacturer:XinXiang Alpha Manufacturing Ltd
Address: West Of Bei Hean Road, Muye District,
 Xin xiangCity,He Nan Province,China,Post Code 453000