Orange Fizz

Orange Fizz

A simple investigation using materials at home


•An orange

•1/2 teaspoon baking soda


•Cut the orange into slices or peel separate into sections.

•Dip a slice or section into the baking soda.

•Take a bite!

As you chew, it should start to bubble in your mouth. How does it work? When acids and bases mix, you get some exciting chemistry! Oranges and other citrus fruits are filled with citric acid. It is a safe acid, and it’s what gives oranges, lemons, and limes their sourness. Baking soda is a base, the opposite of an acid. It’s also safe, but doesn’t taste very good on its own, and will give you a tummy ache if you eat a lot of it. As the citric acid and baking soda mix, it makes millions of carbon dioxide bubbles, the same gas you breathe out, and the same one that makes soda so fizzy.