Question

For the reaction,
${Br}_2\left(l\right)+{Cl}_2\left(g\right)⟶2BrCl\left(g\right)$
$\Delta H=29.37kJ{mol}^{-1};\Delta S=104J{mol}^{-1}$. Find the temperature above which the reaction would become spontaneous.

• A. Above $273.4K$
• B. Above $283.4K$
• C. Above $282.4K$
• D. Above $373.4K$

Answer 1

The correct option is C Above $282.4K$

We have,

$\Delta G=\Delta H-T\Delta S$

so, spontaneous reaction we have $\Delta G<0$

so $\Delta H-T\Delta S<0$

$29370-T\ast 104<0$

so, temperature should be above 282.4 K