# Milk fat is present in milk. Whole milk usually contains about 5.0% milk fat by volume. If I drink a glass of milk with a volume of 250 mL, what volume of milk fat have I consumed?

Dec 25, 2014

The answer is $12.5 m L$.

Percent concentration by volume is defined as the volume of the solute divided by the total volume of the solution and multiplied by 100%. Mathematically, this can be written as

c_(volume) = V_(solute)/(V_(solution)) * 100%

Since you know that your concentration has 5% milk fat by volume, and that the volume of the solution is $250 m L$, you can determine the volume of fat from

V_(solute) = (c_(volume) * V_(solution))/(100%) = (5.0% * 250 mL)/(100%) = 12.5mL

This means that every 250-mL gglass of milk has $12.5 m L$ of fat and $250 - 12.5 = 237.5 m L$ of other stuff (proteins, vitamins, carbohydrates - in the form of lactose, etc).