WEBVTT

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Here is the problem: At what temperature does 1 mol of gas fill 20 L at 760 mmHg?

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Solve PV equals nRT for T, with pressure in mmHg, volume in litres, amount in moles and temperature in kelvin.

3
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Choose the gas constant to match the units. Pressure is in mmHg and volume in litres.

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Rearrange PV equals nRT for T and substitute.

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So the answer is T equals 243.732 K (negative 29.4181 °C).

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An ideal gas obeys PV equals nRT: pressure times volume is proportional to the amount of gas and its absolute temperature. Real gases follow it closely at low pressure and high temperature.

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PV equals 15200 and nRT equals 15200, which agree.