Give the names of the elements represented by the following symbols:

(a) B

(b) He

(c) Si

(d) Be

(e) Li

(f) P

(g) K

(h) F

Define a pure substance.

Define:

(a) Elements

(b) Compounds.

Give two examples for each of the following:

(a) Non-metals which are solids

(b) Metals which are soft

(e) Non-metals which are lustrous

(d) Elements which are liquids

(e) Inert gases