Chemistry 0620 · IGCSE · Preparation of salts

Preparation of salts — practice question

This question concerns sulfuric acid, $\text{H}_2\text{SO}_4$, and the salts that can be prepared from sulfuric acid.
(a(i))[3]

State the temperature and pressure used for stage 2. Name the catalyst used in stage 2.

(a(ii))[1]

Write the chemical equation for the stage 3 reaction.

(a(iii))[1]

Name the substance that reacts with oleum in stage 4.

(b)[1]

Name the black solid formed when concentrated sulfuric acid is added to sugar, $\text{C}_{12}\text{H}_{22}\text{O}_{11}$.

(c(i))[3]

Calculate the volume of 0.0625 mol/dm$^3$ dilute sulfuric acid that will react completely with 25.0 cm$^3$ of 0.100 mol/dm$^3$ potassium hydroxide, KOH, to make aqueous potassium sulfate. Use the steps below.

(c(ii))[1]

Use your answer to c(i) together with the equation to work out the volume of $\text{H}_2\text{SO}_4$ needed.

(d(i))[1]

A flame test is performed on aqueous potassium hydrogensulfate.

(d(ii))[2]

Solid copper(II) carbonate is introduced to aqueous potassium hydrogensulfate.

(d(iii))[1]

A solution containing aqueous barium ions, $\text{Ba}^{2+}(aq)$, is added to aqueous potassium hydrogensulfate.

(e)[3]

Write the ionic equation for the reaction in d(iii), including state symbols.

Worked solution & mark scheme

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