Q.Compare chemical properties of metals and non metals.

Step 1. Electron behaviour. Metals have low ionization enthalpies and readily LOSE valence electrons to form cations; nonmetals have highly negative electron gain enthalpies and readily GAIN electrons to form anions (section 7.5.3.2).

Step 2. Oxide/acid-base character. Metal oxides are typically basic (react with acids, e.g. Na2O + 2HCl → 2NaCl + H2O); nonmetal oxides are typically acidic (react with bases, e.g. Cl2O7 gives HClO4 with water) — established in Problem 7.9 and section 7.5.3.3.

Step 3. Physical property. Metals are good electrical conductors; nonmetals are generally poor conductors (section 7.5.3.2). …

Contrasting metals and nonmetals across electron behaviour, oxide character, conductivity and …

• Comparing only ONE property (e.g. only conductivity) instead of covering electron behaviour, oxide nature, and the periodic trend together. …