A bottle of wine contains 10.5% ethanol by volume. The density of ethanol (C2H5OH) is 0.789 g/cm3. Calculate the concentration of ethanol in wine in terms of mass percent and molality. mass percent

Answer : The mass percent and molality of ethanol is, 8.28 % and 1.96 mol/kg respectively.

Explanation :

As we are given that 10.5 % ethanol by volume. That means, 10.5 mL of ethanol present in 100 mL of solution.

Density of ethanol =

First we have to calculate the mass of ethanol.

Now we have to calculate the volume of water.

Volume of water = Volume of solution - Volume of ethanol

Volume of water = (100 - 8.28) cm³

Volume of water = 91.7 cm³

Now we have to calculate the mass of water.

Density of water = 1.00 g/cm³

Total mass = 8.28g + 91.7g = 99.98 g

Now we have to calculate the mass percent of ethanol.

Mass percent of ethanol =

Now we have to calculate the Moles of ethanol.

Now we have to calculate the molality of ethanol.

Therefore, the mass percent and molality of ethanol is, 8.28 % and 1.96 mol/kg respectively.

the volume increases

the correct answer is:

a. formation of precipitation