How much heat is evolved when 878 kg of ammonia is produced according to the following equation?
N2(g) + 3H2(g) 2NH3(g) ΔH = -91.8 kJ
91.8 kJ x [878,000/(2*17)]= ??
878000g/34g/mol) * (91.8kJ/mol)
moles
To determine the amount of heat evolved when 878 kg of ammonia is produced, you can use stoichiometry and the given enthalpy change (ΔH) of the reaction.
First, you need to convert the mass of ammonia to moles. The molar mass of ammonia (NH3) is calculated by adding up the atomic masses of nitrogen (N) and hydrogen (H):
Molar mass of NH3 = (1 * atomic mass of N) + (3 * atomic mass of H)
Next, calculate the number of moles of ammonia by dividing the mass given by the molar mass:
Number of moles of NH3 = mass of NH3 / molar mass of NH3
Now, you can use the stoichiometric ratio from the balanced equation to determine the moles of nitrogen (N2) and hydrogen (H2) required to produce the given amount of ammonia.
From the balanced equation:
1 mole of N2 reacts with 3 moles of H2 to produce 2 moles of NH3
Therefore, you can calculate the moles of N2 required:
Moles of N2 = (2/1) * moles of NH3
And the moles of H2 required:
Moles of H2 = (3/1) * moles of NH3
Now, with the moles of N2 and H2, you can use the enthalpy change (ΔH) provided in the question to calculate the heat evolved in the reaction.
The enthalpy change (ΔH) is given as -91.8 kJ for the overall reaction, which means it corresponds to the formation of 2 moles of NH3.
To calculate the heat evolved in the reaction, you can use the formula:
Heat evolved = (ΔH / moles of NH3 in the balanced equation) * moles of NH3 produced
Substituting the values:
Heat evolved = (-91.8 kJ / 2) * moles of NH3 produced
Finally, multiply the heat evolved by the molar mass of NH3 to obtain the heat evolved in kilojoules (kJ):
Heat evolved (kJ) = Heat evolved * molar mass of NH3
Calculate all the values using the given mass of ammonia (878 kg), and you will obtain the amount of heat evolved.