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. 847 K
B. 1118 K
C. 1008
D. 1200 K

Answer

B

Explanation

`DeltaG^(@) = DeltaH^(@) -TDeltaS^(@)`
for a spontaneous process `DeltaG^(@) lt 0`
`implies DeltaH^(@)-TDeltaS^(@) lt 0 implies TDeltaS^(@) gt DeltaH^(@) implies T gt (DeltaH^(@))/(DeltaS^(@)) implies T gt (179.1 xx 1000)/(160.2) implies T gt 1117.9 K = 1118 K`.