Answer to Question #140227 in Inorganic Chemistry for Christine

Question

5. 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.
a. Write a balanced thermochemical equation for the reaction.
b. Using Table 8.3, calculate ∆Hof for calcium cyanamide.

Answer 1

When 1 mole of calcium carbonate reacts with ammonia to form calcium cyanamide and liquid water 90.1 kJ of heat is absorbed.

The thermochemical equation for the reaction is as follows:

A).

CaCo_3(s) + 2 NH_3(g) - CaCN_2(S) + 3H₂O_(l)

ΔH_f^O = +90.1KJ