Why Must We Use Absolute Temperature for Ideal Gas Law?

Thread starter jack1234
Start date Dec 1, 2007
Tags

celsius Kelvin

AI Thread Summary

The ideal gas law requires absolute temperature in Kelvin to ensure accurate calculations, as using the Celsius scale can yield nonsensical results. Celsius can produce negative values, which would incorrectly suggest that gas pressure could be zero at temperatures above absolute zero. Absolute zero, defined as 0K, is the point where molecular motion ceases, making it the true baseline for temperature measurements. Therefore, using Kelvin prevents mathematical inconsistencies and aligns with the physical behavior of gases. Accurate application of the ideal gas law hinges on this fundamental requirement of absolute temperature.

Dec 1, 2007

jack1234

Question
Why must we use absolute temperature in the ideal gas law (PV = NkT)?
Why using the Celsius scale would give nonsensical results?

I am not sure what is the reason, can anyone helps?

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Dec 1, 2007

fotisz

The temperature measured in Kelvin degrees cannot ever be negative.

Dec 1, 2007

Dick

Science Advisor

Homework Helper

At 0C the pressure in an ideal gas is not zero. It's zero at absolute zero. Which is 0K.

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