Questions: Wine goes bad soon after opening because the ethanol (CH3CH2OH) in it reacts with oxygen gas (O2) from the air to form water (H2O) and acetic acid (CH3COOH), the main ingredient of vinegar. What mass of ethanol is consumed by the reaction of 2.4 g of oxygen gas? Be sure your answer has the correct number of significant digits.

Wine goes bad soon after opening because the ethanol (CH3CH2OH) in it reacts with oxygen gas (O2) from the air to form water (H2O) and acetic acid (CH3COOH), the main ingredient of vinegar.

What mass of ethanol is consumed by the reaction of 2.4 g of oxygen gas? Be sure your answer has the correct number of significant digits.

Transcript text: Wine goes bad soon after opening because the ethanol $\left(\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{OH}\right)$ in it reacts with oxygen gas $\left(\mathrm{O}_{2}\right)$ from the air to form water $\left(\mathrm{H}_{2} \mathrm{O}\right)$ and acetic acid $\left(\mathrm{CH}_{3} \mathrm{COOH}\right)$, the main ingredient of vinegar. What mass of ethanol is consumed by the reaction of 2.4 g of oxygen gas? Be sure your answer has the correct number of significant digits.

Solution

Solution Steps

Step 1: Write the Balanced Chemical Equation

The chemical reaction for the oxidation of ethanol to acetic acid is:

\[ \text{C}_2\text{H}_5\text{OH} + \text{O}_2 \rightarrow \text{CH}_3\text{COOH} + \text{H}_2\text{O} \]

Balancing the equation, we get:

\[ \text{C}_2\text{H}_5\text{OH} + \text{O}_2 \rightarrow \text{CH}_3\text{COOH} + \text{H}_2\text{O} \]

This equation is already balanced.

Step 2: Calculate Moles of Oxygen Gas

The molar mass of oxygen gas ($\text{O}_2$) is $32.00 \, \text{g/mol}$.

\[ \text{Moles of } \text{O}_2 = \frac{2.4 \, \text{g}}{32.00 \, \text{g/mol}} = 0.075 \, \text{mol} \]

Step 3: Determine Moles of Ethanol Consumed

From the balanced equation, 1 mole of $\text{O}_2$ reacts with 1 mole of $\text{C}_2\text{H}_5\text{OH}$. Therefore, 0.075 moles of $\text{O}_2$ will react with 0.075 moles of $\text{C}_2\text{H}_5\text{OH}$.

Step 4: Calculate Mass of Ethanol Consumed

The molar mass of ethanol ($\text{C}_2\text{H}_5\text{OH}$) is $46.08 \, \text{g/mol}$.

\[ \text{Mass of } \text{C}_2\text{H}_5\text{OH} = 0.075 \, \text{mol} \times 46.08 \, \text{g/mol} = 3.456 \, \text{g} \]