Question

For the decomposition of ozone in oxygen
$O_3\left(g\right)⟶O_2\left(g\right)$

• A. ${\Delta }_{r}H=-ve$
• B. ${\Delta }_{r}S=-ve$
• C. ${\Delta }_{r}G=-ve$ at only low temperature
• D. ${\Delta }_{r}G=-ve$ at only high temperature

Answer 1

The correct option is A ${\Delta }_{r}H=-ve$

$O_3\left(g\right)⟶O_2\left(g\right)$

as $O_2$ is more stable than $O_3$

(Refer to Image)

Therefore the product will have lesser energy than the reactant. Hence on formation of product the energy will release and the reaction will be exothermic.

Therefore, $\Delta H$= negative.