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Derivation of gas constants using molar volume and STP

This video explains the ideal gas law, focusing on the constant 'R'. It demonstrates how 'R' remains the same for any ideal gas, regardless of changes in other variables. The video also clarifies the calculation of 'R' under standard temperature and pressure (STP) using different units of measurement. Created by Ryan Scott Patton.

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• Wont the molecular mass or size of the gas affect the volume of gas as the size of the molecule would change? This would give us variations in volume for constant no. of moles.....
How do we solve that?
• I think that's why the ideal gas equation makes the assumption that the molecules themselves have negligible volume compared to the total volume of the gas so even if the volumes change, the change is so small that it will not affect your results using the ideal gas equation.
• How is it determined that 1 mol of any gass occupies 22.4 liters? Is this the point at which adding more any more gas would result in condensation to liquid phase?
• if 224 L of natural gas are burned in this fuel cell at STP, how many moles of carbon monoxide and hydrogen gases are produced?

• PV = nRT
1 atm X 224 L = n (0.0821)(273 K)
Solve for n, and that will give you the combined moles.
(1 vote)
• why is 1 mole of a gas 22.4l at stp? how do we know that?
• We know this due to theory and some experiments.
(1 vote)
• What do PV and nT represent? What are they?
(1 vote)
• P represents pressure--either in atmosphere or pascals. V represents volume--cubic meters or liters. n = #of moles. T =temperature in kelvins.
• At he says 1 cubic meter is 1000 L. Doesn't this depend on the density of the fluid?
(1 vote)
• Volume and density aren't the same thing. Density measures how much "stuff" occupies a specified volume.

If the mass is greater for substance A compared to substance B, substance A will have larger density than substance B. This is because density is a ratio of mass to volume. However, both substances will occupy the SAME volume.
• Isn't 0 degrees Celcius 273.15 Kelvins? If you put 273.15, I think the constant R will be more exact. Just a wonder.
(1 vote)
• Calculations will be more exact with 273.15 Kelvins instead of 273.
(1 vote)
• C7H16(l) + 11O2(g) --> 7CO2(g) + 8H2O(l)

What volume(in ml) would 0.345 moles of gaseous CO2 occupy at STP?( If STP is 0 degree celsius and 760 torr where 22.4 liters contain one mole.
(1 vote)
• anybody knows what is called a gas?