Chemistry 0620 · IGCSE · Preparation of salts

Preparation of salts — practice question

Methyl orange and methyl red are both dyes that can act as indicators.
(a)[1]

Suggest why the melting point for this sample did not match the true value.

(b)[3]

Use the kinetic particle model of matter to account for this observation.

(c)[1]

What colour does methyl orange turn in dilute sulfuric acid?

(d(i))[2]

Fill in the general word equation for this reaction. metal oxide + acid → [BLANK] + [BLANK]

(d(ii))[1]

Suggest how the leftover copper(II) oxide is removed.

(d(iii))[2]

The statements A to E are provided.

Worked solution & mark scheme

This 10-mark question has a full step-by-step worked solution and mark scheme. One marking point: the sample contains impurities

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