One eight-ounce cup of ice contributes how many milliliters after accounting for melt?

One eight-ounce cup of ice contributes how many milliliters after accounting for melt?

• A. 60 mL
• B. 120 mL
• C. 180 mL
• D. 240 mL

Answer: (B)

The key idea is that melting conserves mass but changes volume because ice is less dense than liquid water. An eight-ounce cup filled with ice holds about 240 milliliters of ice by volume. Ice has a density of roughly 0.92 g/mL, so that ice mass is about 240 × 0.92 ≈ 221 g. When it melts, that mass becomes water with a density of about 1 g/mL, so the melted water volume is about 221 mL. So you’d get roughly 220 mL of water after the ice melts, since the melted water volume is a bit less than the original ice volume due to the density difference.

The key idea is that melting conserves mass but changes volume because ice is less dense than liquid water. An eight-ounce cup filled with ice holds about 240 milliliters of ice by volume. Ice has a density of roughly 0.92 g/mL, so that ice mass is about 240 × 0.92 ≈ 221 g. When it melts, that mass becomes water with a density of about 1 g/mL, so the melted water volume is about 221 mL. So you’d get roughly 220 mL of water after the ice melts, since the melted water volume is a bit less than the original ice volume due to the density difference.