Which volume represents a standard drink for full-strength beer (around 4.8% ABV)?

• A. 350 ml
• B. 200 ml
• C. 285 ml
• D. 60 ml

Answer: (C)

A standard drink is defined as about 10 grams of alcohol. For beer at around 4.8% ABV, you can estimate how much beer contains 10 g of alcohol by looking at how much ethanol is in a given volume. Each 100 mL of beer at 4.8% ABV contains roughly 4.8 mL of ethanol. With ethanol’s density about 0.789 g/mL, that’s about 3.79 g of alcohol per 100 mL. To reach 10 g, you need roughly 10 / 3.79 ≈ 2.64×100 mL, which is about 264 mL. Since standard drinks are often rounded to common serving sizes, 285 mL is used as the typical amount that represents one standard drink for full-strength beer.

So 285 mL best represents one standard drink. The other volumes are either too small or too large to be a single standard drink for this beer strength.