By how many degrees Fahrenheit does the boiling point of water increase if 1 psi of pressure is added?

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Multiple Choice

By how many degrees Fahrenheit does the boiling point of water increase if 1 psi of pressure is added?

Boiling happens when the vapor pressure of water equals the surrounding pressure. If you raise that surrounding pressure by 1 psi, water must reach a higher temperature for its vapor pressure to catch up, so the boiling point shifts upward. Around the normal boiling point, this shift is about 1.8°C per extra psi, which is roughly 3.25°F. This comes from the interplay of the latent heat of vaporization and the large volume change from liquid to steam (the Clapeyron relation). So a 1 psi increase lifts the boiling point by about 3.25°F. This rule of thumb matches practical values used in HVAC and steam tables; for exact numbers, you’d consult precise data, but the ~3.25°F per psi guide is a reliable guide.

Boiling happens when the vapor pressure of water equals the surrounding pressure. If you raise that surrounding pressure by 1 psi, water must reach a higher temperature for its vapor pressure to catch up, so the boiling point shifts upward. Around the normal boiling point, this shift is about 1.8°C per extra psi, which is roughly 3.25°F. This comes from the interplay of the latent heat of vaporization and the large volume change from liquid to steam (the Clapeyron relation). So a 1 psi increase lifts the boiling point by about 3.25°F. This rule of thumb matches practical values used in HVAC and steam tables; for exact numbers, you’d consult precise data, but the ~3.25°F per psi guide is a reliable guide.

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