Chemistry 0620 · IGCSE · The characteristic properties of acids and bases

The characteristic properties of acids and bases — practice question

Solid sodium hydroxide is a base; when it dissolves, it forms NaOH(aq), an aqueous solution.
(a)[1]

State what the term base means.

(b)[1]

State the name given to a base that dissolves to make an aqueous solution.

(c)[1]

State the colour of thymolphthalein in NaOH(aq).

(d)[3]

Complete the word equation for the reaction between NaOH(aq) and ammonium chloride. sodium hydroxide + ammonium chloride → [BLANK] + [BLANK] + [BLANK]

(e(i))[1]

State the name used for metal oxides that react with bases such as NaOH(aq).

(e(ii))[1]

Name one metal oxide that reacts with NaOH(aq).

(f(i))[3]

Complete the dot-and-cross diagram in Fig. 4.1 for a molecule of ethanoic acid.

(f(ii))[1]

Suggest the pH expected for dilute ethanoic acid.

(f(iii))[3]

Complete the symbol equation to show the dissociation of ethanoic acid. CH$_3$COOH [BLANK]

(f(iv))[1]

Write the ionic equation for the reaction when an acid neutralises a soluble base.

(g)[5]

Calculate the concentration of H$_2$SO$_4$, in g/dm$^3$, by carrying out these steps: • Find the number of moles of KOH used. • Work out how many moles of H$_2$SO$_4$ react with the KOH. • Determine the concentration of H$_2$SO$_4$ in mol/dm$^3$. • Determine the concentration of H$_2$SO$_4$ in g/dm$^3$.

Worked solution & mark scheme

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