Question

calculate the molecular mass of the following compound a)water (atomic mass of H=1u and O =16u) b) nitric acid (atomic mass of H=1u N=14u and O=16) c)phosphorus molecules (atomic mass of P=31u)​

Answer 1

To calculate the molecular mass of :-

1) Water

→Chemical Formula of water = $H_2O$

We know that,

atomic mass of H = 1 u

atomic mass of O = 16 u

So, molecular mass of $H_2O$

= 1(2) + 16

= 2 + 16

= 18 u

Answer :- 18 u

2) Nitric acid

→ Chemical formula of Nitric acid = $HNO_3$

So, atomic mass of H = 1 u, O = 16 u and N = 14 u

→ Molecular formula of Nitric acid = 1 + 14 + 16(3)

→ 15 + 48

→ 63 u

Answer :- 63 u

3) Phosphorus molecule

→ Chemical Formula of Phosphorus = $P_4$

→ Atomic mass of Phosphorus = 31 u

→ Molecular mass = 31(4)

→ Molecular mass = 124 u

Answer :- 124 u