Question

calculate the molar mass of the following substances:
(a) Ethyne, C²H²
(b) Sulphur molecule, S
8
(c) Phosphorus molecule, P⁴ (atomic mass of phosphorus =31)
(d) Hydrochloric acid, HCI
(e) Nitric acid, HNO

Please help.

Answer 1

Answer:

Ethyne, C2H2

Molar mass of ethyne

C2H2 = 2 x 12 + 2 x 1

Molar mass of ethyne = 26 g

b Sulphur molecule, S8

Molar mass of sulphur molecule,

S8 = 8 x 32 = 256 g

c Phosphorus molecule, P4 atomicmassofphosphorus=31

Molar mass of phosphorus molecule,

P4 = 4 x 31 = 124 g

d Hydrochloric acid, HCl

Molar mass of hydrochloric acid,

HCl = 1 + 35.5 = 36.5 g

e Nitric acid, HNO3

Molar mass of nitric acid,

HNO3 = 1 + 14 + 3 x 16 = 63 g