Question

Calculate the molar mass of the following :

i. Hydrochloric acid (HCl)

ii. Sodium Sulphate (Na2

SO3 )



iii. Nitric acid (HNO3



iv. Copper Nitrate (Cu(NO3)2)







v. Ethyene (C2H2)

​

Answer 1

Answer:

ANSWER

(a) Ethyne (C

2

H

2

) = 2×Mass of C atom+2×Mass of H atom=2×12+2×1=24+2=26 g/mol

(b) Sulphur dioxide (S

8

)=8×Mass of sulphur atom=8×32=256 g/mol

(c) P

4

=4×Mass of P atom=4×31=124 g/mol

(d) HCl=1×Mass of H atom+1×Mass of Cl atom=1+35.5=36.5 g/mol

(e) HNO

3

=1×Mass of H atom+1×Mass of N atom+3×Mass of O atom

=1×1+1×14+3×16=63 g/mol