1. Which of these is a common household acid?

• A. Soap.
• B. Water.
• C. Salt.
• D. Vinegar.

2. Citric acid is found in oranges and lemons. We can tell the fruit is acidic because it tastes..

• A. sour.
• B. sweet.
• C. cool.
• D. spicy.

3. Strong acids can burn skin and react strongly with metals. Which of these is the hazard symbol for corrosive acids?

A	B	C	D

4. A 'base' is a substance that...

• A. can neutralise an acid.
• B. is solid and acidic.
• C. cannot dissolve in a liquid.
• D. is always neutral.

5. Some bases can dissolve in water. Once dissolved it is called..

• A. a neutral substance.
• B. an alkali.
• C. an oxide.
• D. a concentrated acid.

6. Which one of these is a common alkali?

• A. Water.
• B. Hydrochloric acid.
• C. Sodium hydroxide.
• D. Lemon juice.

7. Substance X is added to an alkali. The two substances react, resulting in a neutral chemical. Substance X Could be....

• A. water.
• B. hydrochloric acid.
• C. sodium hydroxide.
• D. a salt.

8. When red cabbage is boiled in water, a purple liquid is formed. This liquid is a natural indicator.

An indicator is a substance that..

• A. changes colour when an acid / alkali is added.
• B. heats up when an acid / alkali is added.
• C. reacts, producing bubbles when an acid / alkali is added.
• D. produces a solid residue at the bottom when an acid / alkali is added.

9. The pH scale is used to measure acidity and alkalinity. What is the pH of a neutral substance?

• A. 0
• B. 7
• C. 10
• D. 12

10. What is the highest pH value possible?

• A. 1
• B. 7
• C. 14
• D. 20