How Many Molecules Exist in a Cubic Centimeter at 10^-15 atm and 20°C?

Thread starter bse
Start date Feb 19, 2008
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Molecules Vacuum

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The discussion focuses on calculating the number of molecules in one cubic centimeter at a pressure of 10^-15 atm and a temperature of 20°C using the ideal gas law equation PV = nRT. Participants emphasize the importance of correctly identifying the values for pressure, volume, temperature, and the gas constant R. The calculation involves converting the pressure and temperature into appropriate units and determining the number of moles (n) before converting to molecules using Avogadro's number. The extreme low pressure of 10^-15 atm results in a very small number of molecules present in that volume. Understanding these principles is crucial for accurate scientific calculations in low-pressure environments.

Feb 19, 2008

bse

How many molecules exist in one cubic centimeter of space at a pressure of 10^-15 atm and temperature of 20 degrees C?

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Feb 19, 2008

mgb_phys

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PV = nRT
Where P pressure, V volume, T absolute temperature, n number of moles and R is a constant
You can find the units and value of R in the tetbook or wiki.

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