If not handled carefully,ammonium perchlorate can decompose violently according to the thermochemical equation below.
$2 \mathrm{NH}_{4} \mathrm{ClO}_{4}(s) \rightarrow \mathrm{N}_{2}(g) +\mathrm{Cl}_{2}(g) +2 \mathrm{O}_{2}(g) +4 \mathrm{H}_{2} \mathrm{O}(g) \quad\quad\quad\quad\quad \Delta H=-375.6 \mathrm{~kJ}$
The enthalpy of formation of H₂O(g) is ?241.8 kJ.Calculate the enthalpy of formation of ammonium perchlorate.

Question

If not handled carefully,ammonium perchlorate can decompose violently according to the thermochemical equation below.

2 \mathrm{NH}_{4} \mathrm{ClO}_{4}(s) \rightarrow \mathrm{N}_{2}(g) +\mathrm{Cl}_{2}(g) +2 \mathrm{O}_{2}(g) +4 \mathrm{H}_{2} \mathrm{O}(g) \quad\quad\quad\quad\quad \Delta H=-375.6 \mathrm{~kJ}

The enthalpy of formation of H₂O(g) is ?241.8 kJ.Calculate the enthalpy of formation of ammonium perchlorate.

Quizplus · Accepted Answer

The enthalpy change for the reaction is given as -375.6 kJ. Using the enthalpy of formation of water vapor (-241.8 kJ/mol), we can set up the equation: $2 \Delta H_f(\text{NH}_4\text{ClO}_4) = 4(-241.8) - 375.6$. Solving for $\Delta H_f(\text{NH}_4\text{ClO}_4)$ gives -295.8 kJ/mol.

If Not Handled Carefully,ammonium Perchlorate Can Decompose Violently According to the Thermochemical