# R2 | perplexity/sonar-pro | run 2

## Prompt

What is the boiling point of water at sea level, in both Celsius and Fahrenheit? Cite a source.

## Response

Water boils at **100 °C** and **212 °F** at sea level under standard atmospheric pressure (1 atm). This value is widely used as the reference (or “normal”) boiling point of water.

Multiple authoritative sources confirm that at sea level (pressure ≈ 1 atm or 101.3 kPa), **pure water boils at 100 °C (212 °F)**:

- Wikipedia notes that the *normal boiling point* of water is “commonly given as 100 °C (212 °F) … at a pressure of 1 atm (101.325 kPa).”[Boiling point – Wikipedia](https://en.wikipedia.org/wiki/Boiling_point)  
- NASA’s ocean sciences education page states: “Water freezes at 32° Fahrenheit (F) and boils at 212°F (at sea level)… 0° on the Celsius scale is water's freezing point, and 100° is water's boiling point.”[NASA Salinity](https://salinity.oceansciences.org/learn-more.htm?id=13)  
- The Lunar and Planetary Institute explains: “At sea level, pure water boils at 212 °F (100°C).”[LPI – All About Water](https://www.lpi.usra.edu/education/explore/ice/background/allAboutWater/)  
- A University of Maryland chemistry resource similarly states: “For water, the boiling point is 100 degrees Celsius at a pressure of 1 atm.”[UMD Chemistry](https://terpconnect.umd.edu/~wbreslyn/chemistry/pressure/boiling-point.html)  

For practical everyday use, you can safely treat the boiling point of water at sea level as **100 °C (212 °F)**, even though the more precise thermodynamic value is about 99.97 °C (≈211.9 °F) at 1 atm.[Boiling point – Wikipedia](https://en.wikipedia.org/wiki/Boiling_point)  

Would you like a brief explanation of why the boiling point changes with altitude and pressure?
