The equilibrium `N_(2) (g) + O_(2) (g)hArr 2NO (g)` is established in a reaction vessel of `2.5` L capacity. The amounts of `N_(2)` and `O_(2)` taken at the start were respectively 2 moles and 4 moles. Half a mole of nitrogen has been used up at equilibrium. The molar concentration of nitric oxide is:

Options

A. `0.2`
B. `0.4`
C. `0.6`
D. `0.1`

Answer

B

Explanation

`{:(,N_(2) +, O_(2),hArr,2NO),("Initial",2"moles",4"moles",,),("At.Eq.",2-(1)/(2),4-(1)/(2),,2xx(1)/(2)=1"mol"):}`
Molar concentration of NO at equilibrium `=(1)/(2.5) =0.4`