IGCSE Chemistry Acids, bases and salts topical questions

Name the salt formed when each pair of substances reacts.

1. (a)Nitric acid and potassium hydroxide[1]
2. (b)Dilute sulfuric acid and zinc[1]
3. (c)Dilute hydrochloric acid and calcium carbonate[1]

A few drops of litmus solution are added to two unlabelled solutions, X and Y. X turns red and Y turns blue.

1. (a)State the type of solution X is.[1]
2. (b)State the type of solution Y is.[1]

This question is about the reactions of dilute hydrochloric acid.

1. (a)Name the two products of the reaction between dilute hydrochloric acid and magnesium.[2]
2. (b)Describe the test for the gas produced in part (a).[1]
3. (c)Write the word equation for the reaction between dilute hydrochloric acid and aqueous sodium hydroxide.[1]

Zinc carbonate is added to warm dilute sulfuric acid until no more solid dissolves.

1. (a)Name the salt produced.[1]
2. (b)Explain why the zinc carbonate is added in excess.[1]
3. (c)Describe the steps needed after the reaction to obtain pure, dry crystals of the salt.[2]

A student performs a titration between dilute hydrochloric acid and aqueous sodium hydroxide.

1. (a)Name the piece of apparatus used to add the acid in measured volumes.[1]
2. (b)Explain why universal indicator is not suitable for this titration.[1]
3. (c)Describe how the student uses the titration result to obtain pure sodium chloride crystals.[2]

A student prepares crystals of copper(II) sulfate by reacting black copper(II) oxide with warm dilute sulfuric acid.

1. (a)Write the word equation for the reaction.[1]
2. (b)Describe how the student obtains pure, dry crystals of copper(II) sulfate from the reaction mixture.[3]

This question is about ionic equations. (Supplement)

1. (a)Write the ionic equation for the neutralisation of an acid by an alkali.[1]
2. (b)Write the ionic equation for the precipitation of silver chloride when aqueous silver nitrate is mixed with aqueous sodium chloride.[1]
3. (c)Explain why the sodium ions and nitrate ions are not included in the equation in part (b).[1]
4. (d)Name the spectator ions in the reaction between dilute hydrochloric acid and aqueous sodium hydroxide.[1]

Five oxides are listed: Na₂O, SO₃, Al₂O₃, CuO and CO₂.

1. (a)Classify each oxide as acidic, basic or amphoteric.[3]
2. (b)Explain what it means for an oxide to be amphoteric, and why Al₂O₃ fits this description.[2]

Two flasks contain 0.1 mol/dm³ hydrochloric acid and 0.1 mol/dm³ ethanoic acid.

1. (a)State which solution has the lower pH.[1]
2. (b)Explain your answer in terms of dissociation.[2]
3. (c)Write the equation for the dissociation of hydrochloric acid in water.[1]
4. (d)Predict and explain which acid reacts faster with magnesium ribbon.[1]

Lead(II) iodide is a bright yellow insoluble salt. (Supplement)

1. (a)State which method must be used to prepare lead(II) iodide, giving a reason from the solubility rules.[2]
2. (b)Name two aqueous solutions that can be mixed to make it.[1]
3. (c)Write the ionic equation for the reaction.[1]
4. (d)Describe how a pure, dry sample is obtained after mixing.[1]