Question

The reaction of quick lime with water is reversible at the room temperature and at low temperature, therfore,
(A) ΔH and ΔS both +ve
(B) ΔH = +ve and ΔS = -ve
(C) ΔH = -ve and ΔS = +ve
(D) ΔH and ΔS both -ve

Answer 1

i think it could be option C

Answer 2

Answer:

Correct option is (D)

Explanation:

The reaction of quick lime with water is written below:

$CaO (s) + H_2O (l) \rightarrow Ca(OH)_2 (s)$

Sign of $\Delta H$

The given reaction is exothermic in nature.  

Therefore, we can say that a large amount of energy is released in this reaction.

For an exothermic reaction,

$\Delta H\ =\ negative$

Sign of $\Delta S$

Since the randomness is decreasing as we move from reactant to product side, therefore the entropy of the reaction is also negative.

$\Delta S\ =\ negative$