Periodicity (Suggested answer) 1 (a) X3+ (g) → X4+ (g) + e

(ii) E = Aluminum. The difference between 4th electron remove shows that E3+ valence configuration is ns2 np6, while F3+ is (n+1)s1. Therefore, the valence electron configuration of E is (n+1)s2 (n+1)p1. (Cannot use Aluminum as the starting point.)

(iii) B = Neon, J = Argon. (Need to identify)

(c) (i) G: removing electron from s subshell, H: removing electron from a p subshell (from same valence shell.)

The s-subshell is closer to the nucleus than the p-subshell. Electron in the s-subshell, experience greater nuclear attraction than electron in the p-subshell.

Hence, more energy is needed to remove the electron. thus higher 4th IE.

A B C D E F G H I J Successive elements

4th

Ioni

satio

n en

ergy

(b)(i)

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(iii) B removing electron from a lower principal quantum shell, while C removing electron from a higher principal quantum shell.

The lower principal quantum shell is closer to the nucleus.

Electrons in it experiences greater nuclear attraction. More energy is required to remove the electron, hence higher 1st

IE.

(d) Structure: D – Giant Metallic Lattice structure. F – Giant Covalent Structure, H and J – Simple discrete molecule.

Bonds that breaks during melting: D – electrostatic attraction between cation and sea of delocalized electrons. F – Covalent bonds, H and J – van der Waals interaction.

Breaking of inter-atomic bonding requires more energy than van der Waals interaction, hence D and F have higher mp than H and J.

D vs F – more dm3 of bonds are broken in F than in D and hence results in F to have a higher mp.

H vs J – H exists as S8, larger electron cloud and hence more polarisable. Stronger id-id.

Conductivity – D is a metal contains sea of delocalized electron. F – semi-conductor, some electrons that can be delocalized to conduct electricity. H and J do not have charge carriers.

(e) (i) Al2Cl6 (aluminum chloride is not accepted, neither is AlCl3)

(iii) Al2Cl6 (g) → 2AlCl3 (g) As V is a constant, P α n.

(f) Trend : F, H and G. Si (s) → Si (g); ⅛S8 (s) → S (g); ¼P4 (s) → P (g) Si - Giant covalent structure, extensive network of covalent bond. S8 – one mole of S8 breaks 8 moles of S – S bond. P4 – one mole of P4 breaks 6 moles of P – P bond. More bonds are broken in atomization of Si, than P than S (based of atomization equation.)

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