Given the chemical equation:

[tex]\[ C_6H_{12}O_6 \rightarrow 2 C_2H_5OH (aq) + 2 CO_2 (aq) \][/tex]

How many molecules of [tex]\(\text{CO}_2\)[/tex] form when 2.00 g of [tex]\(\text{C}_2\text{H}_5\text{OH}\)[/tex] are produced?



Answer :

To determine the number of molecules of [tex]\(CO_2\)[/tex] produced when 2.00 grams of [tex]\(C_2H_5OH\)[/tex] (ethanol) are produced, we need to follow these steps:

1. Determine the molar mass of [tex]\(C_2H_5OH\)[/tex]:
- The molar mass of [tex]\(C\)[/tex] (carbon) is approximately 12.01 g/mol.
- The molar mass of [tex]\(H\)[/tex] (hydrogen) is approximately 1.01 g/mol.
- The molar mass of [tex]\(O\)[/tex] (oxygen) is approximately 16.00 g/mol.
- Therefore, the molar mass of [tex]\(C_2H_5OH\)[/tex] is calculated as:
[tex]\[ (2 \times 12.01) + (6 \times 1.01) + (1 \times 16.00) = 24.02 + 6.06 + 16.00 = 46.08 \, \text{g/mol} \][/tex]

For the purpose of this calculation, we'll use a rounded value of 46.07 g/mol.

2. Calculate the number of moles of [tex]\(C_2H_5OH\)[/tex] produced:
- Using the formula:
[tex]\[ \text{Number of moles} = \frac{\text{mass}}{\text{molar mass}} \][/tex]
- Inserting the values:
[tex]\[ \text{Number of moles of } C_2H_5OH = \frac{2.00 \, \text{g}}{46.07 \, \text{g/mol}} \approx 0.04341 \, \text{moles} \][/tex]

3. Determine the moles of [tex]\(CO_2\)[/tex] produced:
- According to the balanced chemical equation, 1 mole of [tex]\(C_2H_5OH\)[/tex] produces 1 mole of [tex]\(CO_2\)[/tex].
- Therefore, the number of moles of [tex]\(CO_2\)[/tex] produced is the same as the number of moles of [tex]\(C_2H_5OH\)[/tex] produced.
[tex]\[ \text{Number of moles of } CO_2 = 0.04341 \, \text{moles} \][/tex]

4. Calculate the number of molecules of [tex]\(CO_2\)[/tex] produced:
- Using Avogadro’s number, which is approximately [tex]\(6.022 \times 10^{23}\)[/tex] molecules/mol.
- The formula to calculate the number of molecules is:
[tex]\[ \text{Number of molecules} = \text{Number of moles} \times \text{Avogadro's number} \][/tex]
Substituting the values:
[tex]\[ \text{Number of molecules of } CO_2 = 0.04341 \, \text{moles} \times 6.022 \times 10^{23} \, \text{molecules/mol} \approx 2.614 \times 10^{22} \, \text{molecules} \][/tex]

Therefore, the number of molecules of [tex]\(CO_2\)[/tex] formed when 2.00 g of [tex]\(C_2H_5OH\)[/tex] are produced is approximately [tex]\(2.614 \times 10^{22}\)[/tex] molecules.