A 1.00 g sample of nh4no3 is decomposed in a bomb calorimeter. the temperature increases by 6.12°c. what is the molar heat of decomposition for ammonium nitrate?

First, you have to know that this is an exothermic reaction as the heat increased as a product of the reaction.

then, we need to get the heat change q = M*C*ΔT

= 1 g * 1.23 KJ/C-1 * 6.12

= 7.5 KJ

and because of this is an exothermic reaction so,

the heat of decomposition ΔH = - 7.5 KJ

after that, we need to get the moles of NH4NO3:

moles = mass / molar mass

when the molar mass of NH4NO3 = 80.043 g/mol

∴ moles of NH4NO3 = 1g / 80.043 g/mol

= 0.0125 moles

So the decomposition then will be = ΔH / moles NH4NO3

= - 7.5 KJ / 0.0125 moles

= - 600 KJ. mol-1