Nitric oxide reacts with Br2 and gives nitrosyl bromide as per reaction given below:
2NO (g) + Br₂ (g) ⇌2NOBr (g)

When 0.087 mol of NO and 0.0437 mol of Br₂ are mixed in a closed container at constant temperature, 0.0518 mol of NOBr is obtained at equilibrium. Calculate equilibrium amount of NO and Br₂.

Question

Philoid · Accepted Answer

The chemical reaction is,

Initial amount:

Let x amount of Br₂ be reacted to attain equilibrium. Then amount of substance left at equilibrium,

2NO (g) + Br₂ (g) ⇌2NOBr (g)

Equilibrium amount: 0.087 – 2x 0.0437 – x 2x

Given, equilibrium concentration of NOBr is 0.0518,

i.e, 2x = 0.0518

x = 0.0259

Thus,

Amount of NO at equilibrium = 0.087 - 2 × 0.0259

= 0.0352 mole

Amount of Br₂ at equilibrium = 0.0437 – 0.0259

= 0.0178 mole