1.00 tonne of ammonium from the harber process is reacted with carbon dioxide to prepare the fertiliser urea and 1.35 tonnes of urea are formed.
calculate the percentage yield of urea
74%
To calculate the percentage yield of urea, we use the formula:
Percentage yield = (actual yield / theoretical yield) x 100
First, we need to determine the theoretical yield of urea. From the information given, we know that 1.00 tonne of ammonium reacts to form 1.35 tonnes of urea. Therefore, the theoretical yield of urea is 1.35 tonnes.
Next, we can calculate the percentage yield:
Percentage yield = (1.35 tonnes / 1.35 tonnes) x 100
= 100%
Therefore, the percentage yield of urea is 100%.
To calculate the percentage yield of urea, we need to compare the actual yield of urea to the theoretical yield. The theoretical yield is the amount of urea that would be produced if the reaction went to completion according to the balanced chemical equation.
First, let's determine the number of moles of ammonium (NH4) that reacted by converting the mass given in tonnes to moles. We know that 1 tonne is equal to 1000 kg, and the molar mass of NH4 is 18.04 g/mol.
Mass of NH4 = 1.00 tonne * 1000 kg/tonne * 1000 g/kg = 1,000,000 g
Number of moles of NH4 = Mass / molar mass = 1,000,000 g / 18.04 g/mol = 55,487.28 mol (approximately)
According to the balanced equation, 1 mole of ammonium reacts to produce 1 mole of urea. Therefore, the theoretical yield of urea is also 55,487.28 mol.
Now, we can calculate the actual yield of urea, which is given as 1.35 tonnes. Converting to grams and then to moles:
Mass of urea = 1.35 tonnes * 1000 kg/tonne * 1000 g/kg = 1,350,000 g
Number of moles of urea = Mass / molar mass = 1,350,000 g / 60.06 g/mol = 22,464.07 mol (approximately)
Finally, we can calculate the percentage yield using the formula:
Percentage Yield = (Actual Yield / Theoretical Yield) * 100
= (22,464.07 mol / 55,487.28 mol) * 100
= 40.49%
Therefore, the percentage yield of urea in this reaction is approximately 40.49%.