Are you in the mood for fancy eggs for breakfast? Just add a dash of this magic purple solution and you get … green eggs! The ham is optional.
The explanation behind the color-changing eggs is not magic; it’s science. Most liquids and other substances are an acid or a base. We measure this on a pH scale of 1 to 14. Acids like lemon juice, vinegar or your skin are on the lower half of the scale, between 1 and 6.9. Bases, like milk or egg whites, are higher on the scale, between 7.1 and 14. Pure water is smack dab in the middle at 7.
One way to tell if something is an acid or a base is to use a pH indicator. If you have a fish tank at home, you’ve probably used store-bought pH indicators to test your water. But why buy it when you can make it at home?
Red cabbage is more than a delicious vegetable; it is also a pH indicator. All you need to do to make a pH indicator from your cabbage is to chop some up and boil it in water. After a little bit, the liquid will turn purple, which is great for pH testing. When the purple water is added to a base, like egg whites, it will turn blue or green. Acids will turn it red or pink.
Let’s test it out with the vinegar! Gather the materials below and follow along as we give it a try.
Milk, lemon juice or other acids and bases
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