Question

Deduce the molecular formulae of the compounds formed from the following pairs of elements.
(i) H (valency) and O (valency 2)
(ii) N (valency) and H (valency 1)
(iii) Fe (valency) and S (valency 2)

Answer 1

H2O( water)
NH3(ammonia)
Fe2S3(ferric sulphide)

Answer 2

Answer with explanation:

A molecular formula is a type of chemical formula which shows the number and type of atoms present in a molecule.

From the given information, we are to deduce the molecular formulas of the compounds that can be formed with the given pairs of elements.

(i) H (valency) and O (valency 2):

$H_2O$ - Water

(ii) N (valency) and H (valency 1) :

$NH_3$ - Ammonia

(iii) Fe (valency) and S (valency 2):

$Fe_2O_3$ - Iron (III) Oxide