If `0.5g` of a mixture of two metals A and B with respective equivalent weights 12 and 9 displace 560ml of `H_2` at STP from an acid, the composition of the mixture is

Options

A. `40% A, 60% B`
B. `60% A, 40% B`
C. `30% A, 70% B`
D. `70% A, 30% B`

Answer

A

Explanation

`1 mol" of "H_(2) =22400 mL =2Eq" of "H_(2) , 1 Eq" of "H_(2) =11200 mL`
Eq of `H_(2)=(560)/(11200)=(1)/(20)` Eq , [Let the weight of A be x g, weight of B `=0.5-x`]
Eq of A+Eq of B= Eq of `H_(2) , (x)/(12)+(0.5-x)/(9)=(1)/(20)" ":." " x=0.2`
% of `A=(0.2xx100)/(0.5)=40% , %" of "B=60%`