Table salt, NaCl(s), and sugar, C12H22O11(s), are accidentally mixed. A 5.50-g sample is burned, and 1.70 g of CO2(g) is produced. What was the mass percentage of the table salt in the mixture?
Here is the problem with different numbers I worked a couple of days ago. Just follow the steps.
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To calculate the mass percentage of table salt (NaCl) in the mixture, we need to first determine the amount of NaCl in the 5.50 g sample.
Step 1: Calculate the amount of CO2 produced
The balanced chemical equation for the burning of sugar is:
C12H22O11(s) + 12O2(g) → 12CO2(g) + 11H2O(g)
From the equation, we can see that the molar ratio between sugar (C12H22O11) and CO2 is 12:12, which means that for every 1 mole of sugar burned, 12 moles of CO2 are produced.
We need to find the moles of CO2 produced from the given mass. To do this, we use the molar mass of CO2, which is approximately 44.01 g/mol.
Given: Mass of CO2 produced = 1.70 g
Molar mass of CO2 = 44.01 g/mol
Moles of CO2 = Mass of CO2 / Molar mass of CO2
Moles of CO2 = 1.70 g / 44.01 g/mol
Moles of CO2 ≈ 0.03864 mol
Step 2: Calculate the moles of sugar (C12H22O11)
From the balanced chemical equation, we know that the molar ratio between sugar (C12H22O11) and CO2 is 1:12. Therefore, the moles of sugar can be calculated by multiplying the moles of CO2 by the ratio.
Moles of sugar = Moles of CO2 × (1 mole of C12H22O11 / 12 moles of CO2)
Moles of sugar ≈ 0.03864 mol × (1 / 12)
Moles of sugar ≈ 0.00322 mol
Step 3: Calculate the moles of NaCl
From the balanced chemical equation, there is no direct relationship between NaCl and CO2. Therefore, we need to make an assumption that all the remaining mass in the sample (5.50 g - 1.70 g = 3.80 g) is due to the presence of NaCl.
Molar mass of NaCl = 58.44 g/mol
Moles of NaCl = Mass of NaCl / Molar mass of NaCl
Moles of NaCl = 3.80 g / 58.44 g/mol
Moles of NaCl ≈ 0.06518 mol
Step 4: Calculate the mass percentage of NaCl in the mixture
Mass percentage of NaCl = (Moles of NaCl / Total moles) × 100%
Total moles = Moles of sugar + Moles of NaCl
Total moles ≈ 0.00322 mol + 0.06518 mol
Mass percentage of NaCl = (0.06518 mol / (0.00322 mol + 0.06518 mol)) × 100%
Mass percentage of NaCl ≈ 95.27%
Therefore, the mass percentage of table salt (NaCl) in the mixture is approximately 95.27%.