Acid, Alkali and Salts

Name the products of the reaction between zinc and hydrochloric acid.

• Zinc chloride and hydrogen

• Zinc hydrochloride and water

• Zinc chloride and water

What is the formula of sodium sulfate?

• Na₂SO₄

• Na(SO₄)₂

• Na(SO₃)₂

Which pair of substances do not react together to make copper sulfate?

• Copper and sulfuric acid

• Copper carbonate and sulfuric acid

• Copper oxide and sulfuric acid

In the preparation of zinc chloride crystals from zinc carbonate and hydrochloric acid, why is the mixture filtered after the zinc carbonate has been added to the acid?

• To allow large crystals to form

• To remove excess zinc carbonate

• To remove excess zinc chloride

What is the formula of the ion produced by acids in aqueous solution?

• OH^-

• H⁺

• H^-

In the preparation of a salt, why is the saturated solution of the salt left in a warm, dry place for a few days rather than heated over a water bath?

• To speed up the evaporation of the water

• To allow large crystals to form

• To remove impurities

Which of these pH values is the pH of an acidic solution?

• 7.1

• 7.0

• 6.9

Which of these substances is a weak acid?

• Citric acid

• Hydrochloric acid

• Nitric acid

What is the best definition of a weak acid?

• An acid which is only partially ionised in aqueous solution

• An acid with a pH between 5.0 and 6.9

• A dilute solution of an acid

A acid of concentration 1 mol dm³ has a pH of 2.0. The acid is diluted to a concentration of 0.1 mol dm³. What is its new pH?

• 2.0

• 3.0

• 1.0