Chemistry 0620 · IGCSE · Simple molecules and covalent bonds

Simple molecules and covalent bonds — practice question

Sulfur reacts with chlorine to give two chlorides, P and Q. Chloride P has the formula S$_2$Cl$_2$, while chloride Q has the formula SCl$_2$.
(a)[2]

Both chlorides are covalent and have low melting points. In terms of the attraction between particles, suggest why these chlorides melt at low temperatures.

(b)[1]

Chloride P, S$_2$Cl$_2$, is formed when sulfur reacts with chlorine. Write the symbol equation for this reaction.

(c)[3]

Complete the dot-and-cross diagram in Fig. 3.1 for a molecule of chloride Q, SCl$_2$. Show only outer electrons.

(d)[2]

Suggest two condition changes that would lead to a lower concentration of chloride Q at equilibrium.

(e(i))[1]

Define the term activation energy.

(e(ii))[1]

Give the symbol for activation energy.

(e(iii))[5]

Complete Table 3.1 to show the effect, if any, when the conditions are changed. Use only the words increases, decreases or no change.

(f)[4]

Explain, using oxidation numbers, why: • sulfur is oxidised in the forward reaction • chlorine is oxidised in the reverse reaction.

Worked solution & mark scheme

This 19-mark question has a full step-by-step worked solution and mark scheme. One marking point: attraction between molecules

  • Full mark scheme, point by point
  • Step-by-step worked solution
  • Write your answer & get it marked instantly by AI