Question

Metals reacts with hydrogen halides (such as HCl) to give metal halide and hydrogen:

$M\left(s\right)+nHX\left(g\right)\to M{X}_n\left(s\right)+\frac{1}{2}n{H}_2\left(g\right)$

$△G=△G\left(M{X}_n\right)-n△G\left(HX\right(g\left)\right)$

$△G\left(HCl\right(g\left)\right)=-95.1kJmo{l}^{-1}$

then for the reaction to be product favoured:

• A. $△G$ should be negative and $△G$ for $M{X}_n$ should be more negative than (95.1) $\times$ n J
• B. $△G$ should be negative and $△G$ for $M{X}_n$ should be more negative than (95.1) $\times$ 2n J
• C. $△G$ should be negative and $△G$ for $M{X}_n$ should be more negative than (95100) $\times$ n J
• D. $△G$ should be negative and $△G$ for $M{X}_n$ should be more negative than (95100) $\times$ 2n kJ

Answer 1

Answer: (C)

$△G$ should be negative and $△G$ for $M{X}_n$ should be more negative than (95100) $\times$ n J

If a reaction is to be product-favoured, i.e., it is spontaneous in forward side then $△G$ should be negative and $△G$ for $M{X}_n$ should be greater than and more negative than (95.1) $\times$ n kJ.
So only option C is product favored.

Hence option C is correct.