Sec 3 Chemistry Acids & Bases topical questions

Name the salt formed in each reaction.

1. (a)Zinc + hydrochloric acid[1]
2. (b)Potassium hydroxide + nitric acid[1]
3. (c)Copper(II) oxide + sulfuric acid[1]

Write the word equation, then the balanced chemical equation, for the reaction of magnesium with dilute hydrochloric acid.

State the pH range for acidic, neutral and alkaline solutions.

Classify each oxide as acidic, basic, amphoteric or neutral.

1. (a)Carbon dioxide[1]
2. (b)Magnesium oxide[1]
3. (c)Aluminium oxide[1]
4. (d)Carbon monoxide[1]

Explain the difference between a strong acid and a concentrated acid, using hydrochloric acid and ethanoic acid in your answer.

Write the ionic equation, with state symbols, for the reaction between dilute hydrochloric acid and aqueous sodium hydroxide. Explain why the sodium and chloride ions are omitted.

A student adds dilute hydrochloric acid to three unlabelled white powders: P fizzes giving a gas that turns limewater milky; Q dissolves with no gas and the solution warms; R does not react at all with the acid.

1. (a)Identify the type of substance each powder could be.[3]
2. (b)Name the gas from P and describe its test.[2]

Both sodium oxide and carbon dioxide dissolve in water. Compare the pH and identity of the two solutions, with equations.

20.0 cm³ of gastric juice (hydrochloric acid) is neutralised exactly by 18.0 cm³ of 0.100 mol/dm³ sodium hydroxide (1 : 1 reaction).

1. (a)Calculate the moles of sodium hydroxide used.[2]
2. (b)Calculate the concentration of the hydrochloric acid in mol/dm³.[2]
3. (c)State the pH category (strongly acidic, weakly acidic or neutral) you would expect for gastric juice.[1]

Aluminium oxide is described as amphoteric.

1. (a)State what amphoteric means.[1]
2. (b)Write the equation for aluminium oxide reacting with hot dilute hydrochloric acid.[2]
3. (c)Write the equation for aluminium oxide reacting with hot concentrated sodium hydroxide, and name the salt.[2]

Tablets of pure magnesium hydroxide, Mg(OH)₂ (Mr = 58), each contain 0.29 g of the active ingredient.

1. (a)Calculate the moles of Mg(OH)₂ per tablet.[2]
2. (b)Calculate the moles of hydrochloric acid one tablet can neutralise.[2]
3. (c)Stomach acid is about 0.10 mol/dm³ HCl. What volume of stomach acid does one tablet neutralise?[2]

Flue gases from burning coal contain sulfur dioxide, which causes acid rain. A scrubber sprays the gases with a suspension of calcium oxide.

1. (a)Explain, with an equation, why sulfur dioxide is called an acidic oxide.[3]
2. (b)Write the equation for the scrubber reaction between calcium oxide and sulfur dioxide, and name the salt formed.[3]