Question
Determine if the statement is True or False.
The molar mass of ammonium acetate is 77.083 g/mol. A student uses 0.100 mol of ammonium acetate in a chemical reaction. The student claims that the reaction uses (0.100 mol)(77.083 gmol) = 7.71 g
of ammonium acetate, which has (7.71)(6.022×1023) = 4.64×1024
molecules. Did the student determine the correct number of molecules of ammonium acetate used in the reaction?
(2 points)
Responses
The student calculated the correct number of molecules of ammonium acetate.
The student calculated the correct number of molecules of ammonium acetate.
The student miscalculated the number of molecules of ammonium acetate.
The student miscalculated the number of molecules of ammonium acetate.
The molar mass of ammonium acetate is 77.083 g/mol. A student uses 0.100 mol of ammonium acetate in a chemical reaction. The student claims that the reaction uses (0.100 mol)(77.083 gmol) = 7.71 g
of ammonium acetate, which has (7.71)(6.022×1023) = 4.64×1024
molecules. Did the student determine the correct number of molecules of ammonium acetate used in the reaction?
(2 points)
Responses
The student calculated the correct number of molecules of ammonium acetate.
The student calculated the correct number of molecules of ammonium acetate.
The student miscalculated the number of molecules of ammonium acetate.
The student miscalculated the number of molecules of ammonium acetate.
Answers
GPT-4o mini
To determine whether the student's calculations are correct, we need to review their steps.
1. The student claims that:
\[
\text{Mass of ammonium acetate} = (0.100 \, \text{mol})(77.083 \, \text{g/mol}) = 7.71 \, \text{g}
\]
This calculation is incorrect. The multiplication is not properly executed. The correct calculation should be:
\[
(0.100 \, \text{mol})(77.083 \, \text{g/mol}) = 7.7083 \, \text{g}
\]
which rounds to 7.71 g. So, this part is calculated correctly, by rounding to two significant figures but considered as a mistake since it should ideally have been shown as 7.71 g instead of some confusion in the calculation.
2. Next, the student claims to have calculated the number of molecules using:
\[
\text{Number of molecules} = (7.71 \, \text{g})(6.022 \times 10^{23} \, \text{molecules/mol})
\]
Here, the student mistakenly uses the mass calculated in grams instead of the amount in moles to find the number of molecules.
The correct calculation for the number of molecules based on moles should be:
\[
0.100 \, \text{mol} \times 6.022 \times 10^{23} \, \text{molecules/mol} = 6.022 \times 10^{22} \, \text{molecules}
\]
Therefore, since the student substituted grams instead of moles into the molecule calculation, their final answer is incorrect.
**Conclusion:**
The student's calculations yield an incorrect number of molecules of ammonium acetate used in the reaction.
**The correct response is:**
The student miscalculated the number of molecules of ammonium acetate.
1. The student claims that:
\[
\text{Mass of ammonium acetate} = (0.100 \, \text{mol})(77.083 \, \text{g/mol}) = 7.71 \, \text{g}
\]
This calculation is incorrect. The multiplication is not properly executed. The correct calculation should be:
\[
(0.100 \, \text{mol})(77.083 \, \text{g/mol}) = 7.7083 \, \text{g}
\]
which rounds to 7.71 g. So, this part is calculated correctly, by rounding to two significant figures but considered as a mistake since it should ideally have been shown as 7.71 g instead of some confusion in the calculation.
2. Next, the student claims to have calculated the number of molecules using:
\[
\text{Number of molecules} = (7.71 \, \text{g})(6.022 \times 10^{23} \, \text{molecules/mol})
\]
Here, the student mistakenly uses the mass calculated in grams instead of the amount in moles to find the number of molecules.
The correct calculation for the number of molecules based on moles should be:
\[
0.100 \, \text{mol} \times 6.022 \times 10^{23} \, \text{molecules/mol} = 6.022 \times 10^{22} \, \text{molecules}
\]
Therefore, since the student substituted grams instead of moles into the molecule calculation, their final answer is incorrect.
**Conclusion:**
The student's calculations yield an incorrect number of molecules of ammonium acetate used in the reaction.
**The correct response is:**
The student miscalculated the number of molecules of ammonium acetate.