From the list of characteristics given below, select the five which are relevant to non-metals and their compounds:

A. Ductile

B. Conduct electricity

C. Brittle

D. Acidic oxides

E. Basic oxides

F. Discharged at anode

G. Discharged at cathode

H. Ionic chlorides

I. Covalent chlorides

J. Reaction with dilute sulphuric acid yields hydrogen

K. 1, 2 or 3 valence electrons

L. 5, 6, 7 valence electrons

(Write the five letters corresponding to the correct characteristics)

Why are alkali metals kept in kerosene oil?

Why do gold ornaments look new even after several years of use?

From the metals : copper, iron, magnesium, sodium and zinc, select a different metal in each case which :

(a) does not react with dilute hydrochloric acid,

(b) can form 2+ and 3+ ions,

(c) arrange the above metals in the decreasing order of reactivity.