Question

learning objective: distinguish short- and long-term effects of alcohol use, including current treatment options.

how much alcohol constitutes a \standard\ drink?

a.) 0.4 fluid ounces or 14.4 ml of pure alcohol
b.) 0.2 fluid ounces or 12.2 ml of pure alcohol
c.) 0.6 fluid ounces or 17.7 ml of pure alcohol
d.) 0.9 fluid ounces or 18.8 ml of pure alcohol

Explanation:

Identify the standard definition of a drink

In the United States, a "standard" drink contains roughly 14 grams of pure alcohol.

Convert mass of alcohol to volume

Using the density of ethanol (\(\approx 0.789 \text{ g/ml}\)):

$$ \text{Volume} = \frac{14 \text{ g}}{0.789 \text{ g/ml}} \approx 17.7 \text{ ml} $$

Convert volume to fluid ounces

Converting milliliters to US fluid ounces (\(1 \text{ fl oz} \approx 29.57 \text{ ml}\)):

$$ \text{Volume} = \frac{17.7 \text{ ml}}{29.57 \text{ ml/fl oz}} \approx 0.6 \text{ fl oz} $$

Answer:

• a.) 0.4 fluid ounces or 14.4 ml of pure alcohol
• b.) 0.2 fluid ounces or 12.2 ml of pure alcohol
• c.) 0.6 fluid ounces or 17.7 ml of pure alcohol (Correct answer)
• d.) 0.9 fluid ounces or 18.8 ml of pure alcohol