Key learning points

1. Edible acids have a sour taste.
2. A base is any substance that reacts with acids to form a compound called a salt.
3. Alkalis are soluble bases, and form alkaline solutions.
4. Some acids and alkalis are corrosive and can cause chemical burns.
5. An acid turns blue litmus paper red, an alkali turns red litmus paper blue.

Keywords

• Acid - a solution that has a pH of less than 7.

• Base - a substance that reacts with an acid to form a compound called a salt.

• Alkali - a soluble base that has a pH of greater than 7.

• Litmus paper - used to test if a solution is an acid or an alkali.

• Corrosive substance - can react to damage substances or cause chemical burns on skin.

Common misconception