Wikijunior:Big Book of Fun Science Experiments/Acid Investigations

From Wikibooks, the open-content textbooks collection

These are the types of food and drink that contain acid:

Foods:Lemons,oranges,grapes,grapefruits,tomatoes.

Drinks:Fruity drinks and fizzy drinks.

Experiment:First get a glass of milk. Then slice a lemon in half and squeeze one half until the drops of lemon juice come out. Have the glass of milk ready underneath. Then taste. Is there any difference?

[edit] Principle

The milk should taste considerably different. The reason why the small quantities of juice from the lemon create such a huge impact on the overall taste of the milk is because lemons have large quantities of Citric Acid. Citric Acid is common in many food stuffs because it cheap and potent (meaning that it has a strong taste).

Acidity is a measurement of the activity of hydrogen atoms in a molecule. This is measured on something called a “pH” scale, where anything below a 7 is an acid, anything above a 7 is a base. When the acid and base mix, they create a reaction, which breaks bonds between the molecules of the acids and bases. In some cases, this reaction can produce heat (which is why many cartoons show acids as being able to burn through steel and other materials).