Question

give balanced equations for the following reactions of synthesis involving formation of :
(a) An acid - from sulphur dioxide gas
(b) An alkali - from a basic oxide - sodium oxide
(c) A salt - from a trivalent metal and a coloured gas

Answer 1

a) SO2 + H2O -----> H2SO3

Answer 2

Answer: Synthesis is a type of chemical reaction in which two reactants combine to give a single product.

a) An acid - from sulphur dioxide gas

An acid is a substance which dissociates in water to give $H^+$ ions.

$SO_2+H_2O\rightarrow H_2SO_3$

(b) An alkali - from a basic oxide - sodium oxide

$Na_2O+H_2O\rightarrow 2NaOH$

An alkali is a substance which dissociates in water to give $OH^-$ ions.

(c) A salt - from a trivalent metal and a coloured gas

Aluminium is a metal with atomic no 13.

$Al:13:1s^22s^22p^63s^23p^1$

It can lose 3 electrons to attain stable configuration and thus is trivalent. Bromine is brownish red in color and form aluminium tribromide.

$2Al+3Br_2\rightarrow 2AlBr_3$