CBSE Class 10 Science 2018 · Paper 31(B) · Question 17(a)

(i) Physical properties: 1. Malleability and ductility: metals are malleable and ductile; non-metals are neither malleable nor ductile (solid non-metals are brittle). 2. Conduction: metals are good conductors of heat and electricity; non-metals are poor conductors (except graphite, which conducts electricity). (ii) Chemical properties: 1. Oxides: metals form basic oxides (some, such as aluminium oxide and zinc oxide, are amphoteric); non-metals form acidic or neutral oxides. 2. Nature: metals are electropositive, losing electrons to form positive ions; non-metals are electronegative, gaining electrons to form negative ions. 3. Dilute acids: metals above hydrogen in the reactivity series displace hydrogen from dilute acids; non-metals do not displace hydrogen from dilute acids. Other correct properties also earn credit.