Calcium carbonate, CaCO3 is used as a calcium supplement. When it is heated, it decomposes to form calcium oxide and carbon dioxide. The energy used for the decomposition of calcium carbonate is y kJ. The balanced chemical equation for the reaction is
a) CaCO3(s) → CaO(s) + CO2(g) △H = +y kJ
b) 2CaCO3 (s) → 2CaO(s) + 2C(s) + 2O2(g) △H = +2y kJ
c) CaCO3(s) → CaO(s) + CO2(g) △H = –y kJ
d) 2CaCO3(s) → 2CaO + 2CO2(g) △H = –2y kJ
e) none of the above
The correct balanced chemical equation for the decomposition of calcium carbonate is:
CaCO3(s) → CaO(s) + CO2(g)
And the energy used for the decomposition is given as +y kJ.
Therefore, the correct answer is:
a) CaCO3(s) → CaO(s) + CO2(g) △H = +y kJ