Combined.Lyon

The combined gas law incorporates all the gas laws created by Boyle, Charles, and Gay Lussac. It is written as:

__V1P1__ = __V2P2__ T1    -T2 (the line is just for separation purposes, if its not there the equation appears as though t1 is multiplied by t2)

When dealing with the combine gas law, you will often find yourself dealing with an amount known as "**STP**" or **Standard Temperature Pressure.** The standard temperature pressure is 1 atm for pressure and 273 degrees Kelvin. (also known as 0 degrees celsius or 32 degrees fahrenheit). An example of an equation would be:

If you have a gas in a 100 mL container at 296 K with a pressure of 5 atm, what will the volume be at STP?

Your substituted equation would look like:

__(100mL)(5 atm)__ = __V2 (1 atm)__ 296K  --273

Then, simplify the numerators.

__500 mLK__ = __1atmV2__ 296--273

Isolate the V2 by multiplying by 273 on each side, and divide by 1 atm.

__500mLK • 273K__ = V2       296 K • 1 atm

Simplify.

__136500 mLK²__ = 461.149 L  296 Katm

461.149 is your answer!

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