Question

Molar mass of the hydrocarbon (X) which on ozonolysis consumes one mole of O3 per mole of (X) and gives one mole each of ethanal and propanone is _______ g mol-1  
(Molar mass of C : 12 g mol-1 , H : 1 g mol-1)

Answer 1

Correct Answer: 70

The reaction is: \[ \text{CH}_3-\text{C}\equiv\text{CH}-\text{CH}_3 + \text{O}_3 \to \text{CH}_3\text{CHO} + \text{CH}_3\text{COCH}_3 \] 
The hydrocarbon (X) is pent-2-yne (C$_5$H$_8$). \item Its molecular mass is calculated as: \[ 5 \times 12 + 8 \times 1 = 70 \, \text{g mol}^{-1} \]