Question

How to calculate the molar mass of
(i) Ethyne
(ii)Ethene
(iii)Ethane

Answer 1

At. wt. of 1 carbon atom =12
At. wt. of 1 H atom =1

1) ethyne is CH=_CH ( triple bond is present in b/w 2 carbon atom )
molar mass(m.m.) is = C+H+C+H
=12 +1++12+1
=26

2) ethene is CH2=CH2 (double bond is present b/w two carbon atom )

m.m. is = C+H+H+C+H+H
=12+1+1+12+1+1
= 28

3) ethane is CH3-CH3 (single bond is present b/w 2 carbon atom)

m.m. is =C+H+H+H+C+H+H+H
=12+1+1+1+12+1+1+1
= 30