On subjecting 10ml mixture of `N_(2)` and CO to repeated electric spark to form `CO_(2)` and NO, 7 ml of `O_(2)` was required for combustion. What was the mole precent of CO in the mixture ? (All volumes were measured under identical conditions)

Options

A. 60
B. 40
C. 6
D. 4

Answer

A

Explanation

`underset(a)(N_(2))+underset(a)(O_(2)) to underset(2a)(2NO)`
`underset((10-a))(CO)+underset(((10-s))/(2))((1)/(2)O_(2)) to underset((10-a))(CO_(2))`
`a+((10-a))/(2)=7`
`:.` a = 4
volume of CO=6 mL
Mole % of CO =`(6 xx 100)/(10)` = 60