Chemistry 9701 · AS & A Level · Atoms, molecules and stoichiometry

Atoms, molecules and stoichiometry — practice question

The elements in Period 3 of the Periodic Table display differences in behaviour as you move across the period.

(a(i))[3]

Explain the overall rise in melting point from Na to Al.

(a(ii))[3]

Explain the changes in melting points from P to Ar.

(a(iii))[1]

Explain why Si has a much higher melting point than any of the other elements in the period.

(b(i))[1]

Explain why the first ionisation energy of Ar is greater than that of Cl.

(b(ii))[1]

Explain why the first ionisation energy of Al is less than that of Mg.

(b(iii))[1]

Explain why the first ionisation energy of S is less than that of P.

Worked solution & mark scheme

This 10-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Metallic bonding recognised” …