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Comparing Carbon From Equal-Mass Samples 4 questions
Comparing Carbon From Equal-Mass Samples
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A classroom model compares two samples: acetic acid, C2H4O2, and glucose, C6H12O6. Each pure sample has mass 18.0 g. In a counting simulation, each carbon atom in a sample becomes part of one carbon dioxide molecule. The simulation provides enough oxygen for that conversion.
| Sample | Molecular formula | Molar mass used in model (g/mol) |
|---|---|---|
| Acetic acid | C2H4O2 | 60.0 |
| Glucose | C6H12O6 | 180.0 |
Question 1
Which sample contains more moles of molecules before the conversion?
- Acetic acid
- Glucose
- Both contain the same amount.
- The formulas give no information about the amounts.
Question 2
Calculate the amount of carbon dioxide predicted for each sample. Show how the carbon subscript enters the calculation.
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Question 3
A student sees the same amount of carbon dioxide and concludes that the original samples contained the same number of molecules. Evaluate the claim.
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A new unknown is a pure 18.0 g sample of one of the two substances. An independent model measurement reports 0.100 mol of original molecules.
Question 4
Identify the unknown from the independent record and explain why the carbon dioxide measurement alone could not distinguish it.
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