At what temperature does pure water boil at standard atmospheric pressure (1 atm)?

• A. 100 ^ext{o}C
• B. 212 ^ext{o}F
• C. 373 ^ext{K}
• D. 0 ^ext{o}C

Answer: (A)

Verified step by step guidance

1. Understand that the boiling point of a liquid is the temperature at which its vapor pressure equals the external pressure. For water at standard atmospheric pressure (1 atm), this is a well-known reference point.
2. Recall that standard atmospheric pressure is defined as 1 atm, which is the pressure at sea level.
3. Recognize that the boiling point of pure water at 1 atm is commonly used as a standard temperature reference in chemistry and is typically given in Celsius, Fahrenheit, and Kelvin scales.
4. Know the conversion relationships between temperature scales: Celsius to Kelvin is \(T(K) = T(^\text{o}C) + 273.15\), and Celsius to Fahrenheit is \(T(^\text{o}F) = \frac{9}{5} T(^\text{o}C) + 32\).
5. Use these known values and conversions to identify that water boils at 100 \(^\text{o}C\), which corresponds to 212 \(^\text{o}F\) and 373 K at 1 atm pressure.