00:01
Good day.
00:01
The topic is about ideal gas.
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Assume that gas behaves as an ideal gas, then we can relate the pressure, volume, temperature, and the amount in most of the gas, using the ideal gas law.
00:12
B is equal to nrt over v, where b is the pressure in atmosphere or atm, n is the most, r is the gas constant, which is equal to 0 .08 to 1 -21 -liter's atmosphere per mole kelvin, t is the temperature in kelvin, and v is the volume in liter.
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We note that we can take on several units or combination, of units for r depending on the unit of p, t, and v.
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Suppose we have an air that contains 10 grams of oxygen at temperature of 273 kelvin and one atmosphere.
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We wish to find the volume of that air.
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And also we wish to first establish how much in terms of mole fraction is oxygen gas in air.
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We note that oxygen gas, or air, rather, is composed of 79 % by moles of nitrogen, 20 % by mole of oxygen, and the rest, which is 1 % is other gases.
01:21
And this is a fact.
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So the moles of our mole fraction of oxygen in air is equal to 0 .20.
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And this means that for every mole of air, there is 0 .2 mole of oxygen.
01:43
So we can have this.
01:45
We can write it as this.
01:48
All right.
01:49
So now let's do letter b...