Calculating the Moles of Ethanol in a Bottle of Wine

How many moles of ethanol are in a 750-mL bottle of wine that is approximately 12% ethanol by volume?

Final Answer:
In a 750-mL bottle of wine, which is approximately 12% ethanol by volume, there are roughly 1.542 moles of ethanol, calculated using the density and molar mass of ethanol.

To calculate the number of moles of ethanol present in a 750-mL bottle of wine, we need to first determine the volume of ethanol. Since wine is approximately 12% ethanol by volume, a 750-mL bottle of wine contains 0.12 × 750 mL = 90 mL of ethanol. Next, we convert this volume to mass using the density of ethanol, which is 0.789 g/mL. Therefore, the mass of ethanol is 90 mL × 0.789 g/mL = 71.01 g.

Now that we have the mass of ethanol, we can use the molar mass of ethanol, which is 46.06 g/mol, to find the number of moles. The number of moles of ethanol is the mass divided by the molar mass: 71.01 g ÷ 46.06 g/mol = 1.542 moles. Thus, in a 750-mL bottle of wine, there are approximately 1.542 moles of ethanol.