Fizz Test

Many drinks are “carbonated”. These drinks fizz and foam, releasing bubbles of the gas carbon dioxide. Carbon dioxide is also present sometimes in solids. Baking Soda (also called Sodium Bicarbonate) is one solid that can release carbon dioxide bubbles.

You will run several tests to see which ingredient helps release carbon dioxide bubbles from Sodium Bicarbonate.

Measuring spoons
liquid measuring cup
4 large water glasses
sugar, baking soda
artificial sweetener
citric acid
long teaspoon for stirring
pen
paper for labeling (optional)

Line up the drinking glasses, and use the measuring cup to measure and pour 4 ½ ounces (133 mL) of water into each one.

Add a ¼ teaspoon of baking soda (Sodium Bicarbonate) to all the drinking glasses, and stir them with the long teaspoon.

Label the first glass sugar, the second glass artificial sweetener, the third citric acid, and the last you can leave
blank or label control. You will not put any additional ingredient in this glass. The control glass helps you determine if there is anything different or varying going on in the other glasses.

In the first glass, measure and add ¼ teaspoon of sugar. Use the long teaspoon to stir the contents of the glass. Observe and compare it to the control glass.

In the second glass, measure and add ¼ teaspoon artificial sweetener. Use the long teaspoon to stir the contents of the glass. Observe and compare it to the control glass.

In the third glass, measure and add ¼ teaspoon citric acid. Use the long teaspoon to stir the contents of the glass. Observe and compare it to the control glass.

Which ingredient did the best job of getting the carbon dioxide bubbles out of the sodium bicarbonate? Is it still fizzing? Does it make a sound? What happens if you stir it again? Is there any powder left in the bottom? How long will it fizz?

What’s happening: You should have created a chemical reaction with sodium bicarbonate, citric acid, and water. The sodium bicarbonate combined with the citric acid to release carbon dioxide in the form of bubbles. Left in the cup is the water and a byproduct called sodium citrate.