Question

For the gas phase reaction,
PCI (g) = PCI (9) + Cl (g), which of the
following conditions is correct ?
[AIPMT (Prelims)-2008]
(1) AH > 0 and AS < 0
(2) AH = 0 and AS < 0
(3) AH > 0 and AS > 0
(4) AH < 0 and AS < 0

Answer 1

Answer:

The answer may be 3rd option

Explanation:

∆H=∆U+∆nRT

For the above reaction ∆n=1

So ∆H is greater than 0

And ∆S is the measure of randomness and in the above equation number of gas molecules increases hence the randomness increases hence ∆S is greater than 0

Answer 2

Answer:(for rxn delta n =2-1=1)

So deltaH=delta + nRT

H=E + Rt and E=H-Rt

So H greater than E

Also H greater than 0

Explanation: