Nitration of 1.70 g of methyl benzoate (M_r = 136.0) produces methyl 3-nitrobenzoate (M_r = 181.0) - AQA - A-Level Chemistry - Question 29 - 2021 - Paper 3
Question 29
Nitration of 1.70 g of methyl benzoate (M_r = 136.0) produces methyl 3-nitrobenzoate (M_r = 181.0). The percentage yield is 65.0%.
What mass, in g, of methyl 3-nitr... show full transcript
Worked Solution & Example Answer:Nitration of 1.70 g of methyl benzoate (M_r = 136.0) produces methyl 3-nitrobenzoate (M_r = 181.0) - AQA - A-Level Chemistry - Question 29 - 2021 - Paper 3
Step 1
Calculate the number of moles of methyl benzoate
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Answer
To calculate the number of moles of methyl benzoate, use the formula:
n=Mm
Where:
m = mass of methyl benzoate = 1.70 g
M = molar mass of methyl benzoate = 136.0 g/mol
Substituting the values:
n=136.0g/mol1.70g≈0.0125mol
Step 2
Determine the theoretical yield of methyl 3-nitrobenzoate
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Answer
The reaction produces 1 mole of methyl 3-nitrobenzoate for every mole of methyl benzoate.
Thus, the theoretical yield in grams can be calculated as:
Theoretical yield(g)=n×M
Where:
n = number of moles of methyl benzoate = 0.0125 mol
M = molar mass of methyl 3-nitrobenzoate = 181.0 g/mol
Calculating:
Theoretical yield=0.0125mol×181.0g/mol≈2.26g
Step 3
Calculate the actual yield using the percentage yield
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Answer
The actual yield can be determined using the percentage yield formula:
Actual yield=(100Percentage yield)×Theoretical yield
Given that the percentage yield is 65.0%:
Actual yield=(10065.0)×2.26g≈1.47g
Thus, the mass of methyl 3-nitrobenzoate produced is approximately 1.47 g.