When one mole of calcium carbonate reacts with ammonia, solid calcium cyanamide, CaCN2, and liquid water are formed. The reaction absorbs 90.1 kJ of heat. Write a balanced thermochemical equation for the reaction. Calculate ΔHf° for calcium cyanamide. ΔHf° (kJ/mol) CaCO3(s) –1206.9 NH3(g) –46.1 H2O(l) –285.8

colorless gas, exhibiting a blue glow when placed in an electric field

b) solid

its a type of rock

option c: 1605.1 kj

the balanced chemical reaction for combustion of methane is as follows:

here, enthalpy formation of is -74.7 kj/mol, 0 kj/mol, -393.5 kj/mol and -241.82 kj/mol respectively.

the heat released or can be calculated as follow:

putting the values,

thus, heat released by combustion of 1 mol of methane is 802.54 kj/mol. thus, for 2 mol, heat released will be:

therefore, heat released by the combustion of 2 mol of methane is 1605.1 kj.