Question

The decomposition of N I 3 to form N 2 and I 2 releases − 290.0 kJ of energy. The reaction can be represented as 2N I 3 (s)→ N 2 (g)+3 I 2 (g), ΔH rxn =−290.0 kJ Find the change in enthaply when 10.0 g of N I 3 decomposes. Express your answer to three significant figures and include the appropriate units.

Answer 1

To find the change in enthalpy when 10.0 g of NI3 decomposes, use the concept of stoichiometry and calculate the moles of N2 produced. Then, use the equation ΔH = q/moles to find the change in enthalpy per mole. Finally, divide the given ΔHrxn by the moles of N2 produced.

Step-by-step explanation:

The given reaction is 2NI3 (s) → N2 (g) + 3I2 (g) with ΔHrxn = -290.0 kJ. To find the change in enthalpy when 10.0 g of NI3 decomposes, we need to use the concept of stoichiometry. First, calculate the moles of NI3 using its molar mass. Then, use the mole ratio from the balanced equation to find the moles of N2 produced. Finally, use the equation ΔH = q/moles to find the change in enthalpy per mole. In this case, you would divide the given ΔHrxn by the moles of N2 produced. The final answer should be expressed in kJ/mol, rounded to three significant figures.