## Ideal Gas Laws

charlotte_jacobs_4I
Posts: 63
Joined: Fri Sep 28, 2018 12:29 am

### Ideal Gas Laws

What are the rules and equations that go with ideal gases? Are idea gases noble gases?

Porus_Karwa_2E
Posts: 72
Joined: Fri Sep 28, 2018 12:24 am

### Re: Ideal Gas Laws

The ideal gas laws go with PV=nRT where P is 1atm n is 1 mole of gas.

Xinyi Zeng 4C
Posts: 63
Joined: Fri Sep 28, 2018 12:18 am

### Re: Ideal Gas Laws

Ideal gas and noble gas are two different concepts. The concept of "Ideal gas" based on several basic assumptions (e.g. the gas particles have negligible volume/size compared to the volume of the container; the gas particles exert negligible intermolecular forces on one another). "Ideal gas" can be any gas, as long as they have the ideal behavior. Noble gas just refers to any of the gaseous elements helium, neon, argon, krypton, xenon, and radon (Group 18 of the periodic table).

The relationships between the different variables could be derived from the ideal gas equation:
Boyle's Law: at constant T and n, V and p have an inverse relationship (pV = constant), p1V1 = p2V2
Charles' Law: at constant p and n, V and T have a direct relationship (V/T = constant), V1T1 = V2T2
Avogadro's Law: at constant T and p, V and n have a direct relationship (V/n = constant), V1n1=V2n2
It can be used to determine the molar mass of gases and volatile liquids as n=m(mass)/M(molar mass),
pV=nRT=RT(m/M) -> M=mRT/pV --(1)
It can also be used to determine the density of a gas:
m/V=pM/RT (derived from (1)) -> m/V=pM/RT -> density = pM/RT

deniise_garciia
Posts: 30
Joined: Wed Nov 16, 2016 3:04 am

### Re: Ideal Gas Laws

How can one tell when you must use the ideal gas law?

005199302
Posts: 108
Joined: Fri Sep 28, 2018 12:15 am

### Re: Ideal Gas Laws

When you are given all the components besides for one in the ideal gas law, or if the question states to assume the gas is ideal, it's an indicator that you may need to use the ideal gas law. Also, if you feel you aren't given enough information to solve the question using formulas you've learned in class, try to use the ideal gas law to fill in what's missing.