Respuesta :
Answer:
THE STANDARD ENTHALPY OF FORMATION OF AMMONIA GAS IS 293.75kJ OF HEAT.
Explanation:
To solve this question, you must first write out the equation for the reaction.
Equation:
N2 (g) + 3H2(g) <-------> 2NH3(g)
So therefore, when 50 g of N2 reacts, 164.5 kJ of Heat was liberated.
First equate the number of moles of Nitrogen and ammonia gas
1 mole of N2 produces 2 moles of ammonia
Calculate the molar mass of each variables:
Molar mass of N2 = 14*2 = 28 g/mol
Molar mass of ammonia = ( 14 + 1*3) = 17 g/mol
So, 1 mole of N2 = 2 moles of NH3
28 g/mol of N2 = 17 * 2 g/mol of NH3
If 50 g of nitrogen was used to react with excess hydrogen, the mass of ammonia formed is;
28 g of N2 = 34 g/mol of NH3
50 g of N2 = ( 50 * 34 / 28 ) g of NH3
= 1700 / 28
= 60 .71 g of ammonia.
At standard conditions, 34 g of ammonia will liberate 164.5 kJ of heat. What amonut would be generated by 60.71 g of ammonia?
34 g of ammonia = 164.5 kJ of heat
60.71 g of ammonia = ( 60.71 * 164.5 / 34) kJ of heat
= 9987.5 / 34
= 293.75 kJ of heat.
In other words, the standard enthalpy of formulation for ammonia gas is 293.75 kJ of heat.
