A contributions of both heat (enthalpy) and randomness(entropy) shall be considered to the overall spontaneity of process.When deciding about the spontaneity of a chemical reaction or other process, we define a quantity called the Gibb's energy change (DeltaG). DeltaG=DeltaH-TDeltaS where,DeltaH=Enthalpy change, DeltaS=Entropychange , T=Temperature in kelvin. If DeltaGlt0, Process is spontaneous , DeltaG=0, Process is at equilibrium , DeltaGgt0, Process is non-spontaneous. Quick lime (CaO) is produced by heating limestone (CaCO_3) to drive off CO_2 gas. CaCO_3(s)toCaO(s)+CO_2(g),DeltaH^@=180 KJ,DeltaS^@=150 J//K Assuming that variation of enthalpy change and entropy change with temperature to be negligible, choose the correct option :

A contributions of both heat (enthalpy) and randomness(entropy) shall

1.	A contributions of both heat (enthalpy) and randomness(entropy) shall be considered to the overall spontaneity of process.When deciding about the spontaneity of a chemical reaction or other process, we define a quantity called the Gibb's energy change (DeltaG). DeltaG=DeltaH-TDeltaS where,DeltaH=Enthalpy change, DeltaS=Entropychange , T=Temperature in kelvin. If DeltaGlt0, Process is spontaneous , DeltaG=0, Process is at equilibrium , DeltaGgt0, Process is non-spontaneous. Quick lime (CaO) is produced by heating limestone (CaCO_3) to drive off CO_2 gas. CaCO_3(s)toCaO(s)+CO_2(g),DeltaH^@=180 KJ,DeltaS^@=150 J//K Assuming that variation of enthalpy change and entropy change with temperature to be negligible, choose the correct option :
Answer» Decomposition of `CaCO_s (s)` is NEVER sppotaneous Decomposition of `CaCO_s (s)` becomes spontaneous when temperature is less than `900^@C` Decomposition of `CaCO_3 (s)` becomes non-spontaneous when temperature is greater than `1000^@` Decomposition of `CaCO_3 (s)` becomes spontaneous when temperature is greater than `927^@C` Solution :`T=(DeltaH)/(DELTAS)=(180xx10^3)/150=1200 K` Temperature =1200-273=`927^@C` For `DeltaG lt 0,T gt 927^@C`