Question

$3.2$ moles of hydrogen iodide were heated in a sealed bulb at ${444}^{0}C$ till the equilibrium state was reached. Its degree of dissociation at this temperature was found to be $22$%. The number of moles of hydrogen iodide present at equilibrium are:

• A. $2.496$
• B. $1.87$
• C. $2$
• D. $4$

Answer 1

The correct option is A $2.496$

Concentration of $HI$ is $3.2$

Degree of dissociation= $22$%

Degree of dissociation= $\frac{Numberofmolesdissociated}{Numberofmolespresentinitially}$

$\Rightarrow \frac{22}{100}=\frac{x}{3.2}\Rightarrow x=0.704$

According to reaction-

$2HI\left(g\right)=H_2\left(g\right)+I_2\left(g\right)$

$2M$ $M$ $M$

$2\left(0.352\right)$ $0.352$ $0.352$

$(1-0.22)\times 3.2$

$\Rightarrow 0.78\times 3.2=2.496$