In conversion of lime-stone to lime,
`CaCO_(3(s)) to CaO_((s)) + CO_(2(g))` the values of `DeltaH^@` and `DeltaS^@` are `+179.1 kJmol^(-1)` and `160.2 J//K` respectively at `298K` and 1 bar. Assuming that `DeltaH^@` and `DeltaS^@` do not change with temperature, temperature above which conversion of lime-stone to lime will be spontaneous is :

Options

A. 1008 K
B. 1200 K
C. 845 K
D. 1118 K

Answer

D

Explanation

We know, `Delta G = Delta H - T Delta S`
So, lets find the equilibrium temperature, i.e. at which `Delta G =0`
`Delta H = T Delta S`
`T=(179.1xx1000)/(160.2)=1118 K`
So, at temperature above this, the reaction will become spontaneous.