Question

Ammonia undergoes combustion to yield nitric oxide and water by the following reaction equation: 4 NH3 (g) + 5 O2 (g) → 4 NO (g) + 6 H2O (g) ΔH = - 1170 kJIf 26.5 g of NH3 is reacted with excess O2, what will be the amount of heat given off?

Answer 1

Answer:

-455 kJ

Explanation:

Let's consider the following thermochemical equation.

4 NH₃(g) + 5 O₂(g) → 4 NO(g) + 6 H₂O(g) ΔH = -1170 kJ

1170 kJ of heat are released per 4 moles of NH₃. Considering that the molar mass of NH₃ is 17.03 g/mol, the amount of heat given of by 26.5 g of NH₃ is:

$26.5g.\frac{1molNH_{3}}{17.03g} .\frac{(-1170kJ)}{4molNH_{3}} =-455kJ$