Medium Practice — Set 2

Quick Recap — Anomalies & More Reasoning

• Anomalous fluorine: low F$-$F bond enthalpy (small size, lone-pair repulsion); only $-1$ state; strongest oxidiser.
• Nitrogen cannot expand its octet (no d-orbitals), so it forms no $NCl_5$; Lewis acidity of boron halides: $BF_3<BCl_3<BBr_3$ (back-bonding decreases).
• Hydride stability/reducing power down group 16: $H_2O>H_2S>H_2Se>H_2Te$ (stability), reverse for reducing power.
• Oxyacid acidity rises with the central atom's oxidation state.