What is the percent by volume of ethanol (C2H60 or ethyl alcohol) in the final solution when 45 mL of ethanol is diluted to a volume of 250 mL with water?

Percent by volume = 18%

Explanation:

Given data:

Volume of ethanol = 45 mL

Volume of solution = 250 mL

Solution:

In given problem there is 45 mL of solute while volume of Solvent is,

250 mL - 45 mL = 205 mL

The volume of solution (solvent + solute) = 250 mL

The percent by volume is calculated through following formula:

Percent by volume = Volume of solute / Volume of solution × 100

Percent by volume = 45 mL / 250 mL × 100

Percent by volume = 0.18  × 100

Percent by volume = 18%

there are two significant figures.