0.037g of an alcohol, R-OH was added to C₂H₅Mgl and the has evolved measured 11.2cc at STP. The molecular mass of R-OH will be

Options

(a) 47
(b) 79
(c) 77
(d) 74

Correct Answer:

74

Explanation:

R—OH + C₂H₅Mgl → C₂H₆ + RMgl
0.037 11.2 cc
11.2 cc gas evolved by alcohol= 0.037 g
22400 cc gas will be evolved by alcohol
= 0.037/11.2 x 22400
= 74 g