Question

For the reaction, $2Cl\left(g\right)\to C{l}_2\left(g\right)$, the signs of $△H$ and $△S$ respectively, are:

• A. $+,-$
• B. $+,+$
• C. $-,-$
• D. $-,+$

Answer 1

Answer: (C)

$-,-$

$2Cl\left(g\right)\to C{l}_2\left(g\right)$

Atoms forming a molecule, making system less disordered. Entropy is decreasing $\Delta S(-ve)$ in the reaction. Further the addition reaction is exothermic since a bond is being formed, therefore $\Delta H$ is also $-ve$.