Calcium oxide, CaO, is manufactured by decomposition of calcium carbonate, CaCO3
ID: 841245 • Letter: C
Question
Calcium oxide, CaO, is manufactured by decomposition of calcium carbonate, CaCO3, in a furnace at 500 K: CaCO3(s)CaO(s)+CO2(g) The spontaneity of a reaction can be determined from the free energy change for the reaction, G. A reaction is spontaneous when the free energy change is less than zero. A reaction is nonspontaneous when the free energy change is greater than zero. A reaction is in equilibrium when the free energy change is equal to zero. When adjusted for any changes in H and S with temperature, the standard free energy change GT at 500K is equal to 9.8Ý104J/mol. Calculate the equilibrium constant at 500K . Express your answer numerically to three significant figures.
Explanation / Answer
? G= RTlnK
we have ? G=9.8 x104J/mol
T= 500K
THEREFORE PUTTING IN ABOVE EQUATION
WE GET lnK= ? G/RT
lnK= 9.8 x104J/mol /8.314*500
K=1.73 x 1010