Answer:
Câ‚„Hâ‚„Nâ‚‚
Explanation:
Given that:
M+ = 80.
It implies that the number of nitrogen present in the molecule must also be even according to the Nitrogen rule.
So from the Formula CHN, the nitrogen will have to be 2 because if we make use of 4, it will exceed the given M+ which is 80.
∴
C₄ = 4 × 12 = 48
H₄  = 4 × 1  = 4
Nâ‚‚ =  2 × 14 = 28   Â
           80   Â
As such, the molecular formula of the compound is Câ‚„Hâ‚„Nâ‚‚