At sea level, water freezes at 32 degrees Fahrenheit and boils at what temperature?

• A. 32 degrees Fahrenheit
• B. 100 degrees Fahrenheit
• C. 212 degrees Fahrenheit
• D. 451 degrees Fahrenheit

Answer: (C)

Water boils at sea level when its vapor pressure equals atmospheric pressure, which on the Fahrenheit scale is 212 degrees. Since 0 °C equals 32 °F and 100 °C equals 212 °F, the boiling point in Fahrenheit at standard pressure is 212 °F. The other numbers don’t fit: 32 °F is the freezing point, 100 °F is well below the boiling point (it's about 37.8 °C), and 451 °F is not the boiling point of water at standard pressure.