Question

One mole of $N_2$ and $3$ moles of $H_2$ are mixed in a liter flask. If $50\%$ $N_2$ is converted into ammonia by the reaction, $N_2\left(g\right)+3H_2\left(g\right)\rightleftharpoons 2N{H}_3\left(g\right)$ then the total number of moles of gas at equilibrium is ?

• A. $1.5$
• B. $3.0$
• C. $4.5$
• D. $6.0$

Answer 1

The correct option is B $3.0$

Total no. of moles of gas $=(1-x)+(3-3x)+2x=4-2x$

As 50% of $N_2$ is converted into ammonium,

$3-3x=3\times \frac{50}{100}$

$3-3x=1.5$

$x=0.5$

Now we have to calculate the total no. of moles of gas $=4-2x=4-2\left(0.5\right)=3$

Therefore, total no. of moles of gas = $3$ moles.

Hence, option B is the correct answer.