1. What are the two products which are always formed in the neutralisation reaction between an acid and a base?

a) A salt and hydrogen
b) A salt and carbon dioxide gas
c) A salt and water
d) Carbon dioxide and water

2. What is the key difference between a base and an alkali?

a) Alkalis are acidic but bases are not
b) Alkalis are aqueous solutions and bases are mostly solids
c) Alkalis dissolve in water but bases do not
d) Bases produce hydrogen ions (H⁺) in water while alkalis produce hydroxide ions (OH^-)

3. Which of the following can act as a base?

a) Sodium chloride
b) Copper sulfate
c) Sulfuric acid
d) Calcium carbonate

4. The gas carbon dioxide is released when a metal carbonate neutralises an .

5. When sulfuric acid is neutralised by the base copper oxide a blue solution of sulfate is formed, the other product of this neutralisation reaction is .

6. Which of the following bases is the least soluble in water?

a) Ammonia gas
b) Potassium oxide
c) Sodium hydroxide
d) Copper oxide

7. What does the term anhydrous mean in chemistry?

a) Contains water
b) Very pure
c) Contains no water
d) Colourless

8. Most indigestion tablets contain the base calcium or chalk, this reacts with excess stomach acid to release the gas carbon dioxide, this is why some people often feel after taking an indigestion tablet.

9. What is the purpose of recrystallisation?

a) To increase the rate of reaction
b) To produce a larger amount of product
c) To change the state of the main product
d) To purify solid crystals

10. What is a sharp melting point an indication of?

a) Large crystals
b) The purity of the solid
c) The presence of impurities
d) Small crystals