Step-by-step explanation:
N₂ (g) + 3 H₂ (g) ---> 2 NH₃ (g) ∆H° = - 91.8 kJ/mol
According to the ∆H° of reaction, when 1 mol of NH₃ is produced -91.8 kJ are released. We have to find the moles of H₂ nequired to produce -8301 kJ.
First we have to calculate the number of moles of NH₃ that should be produced in order to release that amount of heat.
moles of NH₃ = -8301 kJ * 1 mol/(-91.8 kJ)
moles of NH₃ = 90.42 mol
According to the coefficients of the reaction's equation 2 moles of NH₃ will be produced by 3 moles of H₂. The molar ratio between H₂ and NH₃ is 3 to 2. We can use that relationship to find the answer to our problem.
3 moles of H₂ = 2 moles of NH₃
moles of H₂ = 90.42 moles of NH₃ * 3 moles of H₂/(2 moles of NH₃)
moles of H₂ = 135.6 moles
Answer: 135.6 moles of H₂ are required.