Ideal Gas Law

The last lesson we learned the first week of the Gas Law unit was the Ideal Gas Law, which revolves around the Kinetic Theory of Gases. In this law...

1. "Gases consist of small particles (molecules) which are in continuous motion
2. "The volume of the molecules present is negligible compared to the total volume occupied by the gas"
3. "Intermolecular forces are negligible"
4. "Pressure is due to the gas molecules colliding with the walls of the container"

Real gases are different from ideal gases because there is less kinetic energy in real gases at low temperatures. So, they are able to attract each other at high pressures because they are closer together so that the volume of the gas molecules becomes significant compared to the volume the gas occupies. 

Below is the formula used for the Ideal Gas Law:

http://dl.clackamas.edu/ch105/lesson1ideal_gas_law.html

P=pressure, V=volume, n=moles, R= gas constant, T= temperature. The gas constant in 0.0821 L atm/ mol K

Here is a link that explains ideal gases more:
Ideal Gas Law

Avogadro's Law and Combined Gas Law

On Wednesday, we learned our third and fourth gas law. Avogadro's law states that volume is directly proportional to the number of moles of gas present as long as there is constant temperature and pressure. So, as the number of moles in a gas increase, the volume will have to increase to maintain that constant pressure and temperature. Here is a picture that represents that concept:

http://wps.prenhall.com/wps/media/objects/4678/4790892/ch09_02.htm

As you can see, the moles and volume doubled to keep the pressure at 1 atm in both cases.

Below is the formula we use in math problems that involve Avogadro's law:

http://me-mechanicalengineering.com/gas-laws/

A helpful fact that comes in handy with some math questions is that the volume of one mole of gas is 22.4 liters. This can be used as a conversion factor.

We also learned about the combined gas law that involves a change in all variables, like moles, volume, temperature, and pressure. It combines all of the gas laws we have learned so far. Here is the formula for it:

http://me-mechanicalengineering.com/gas-laws/

Here are also a couple links that further explain these two laws:

Combined Gas Law

Avogadro's Law

Charles' Law

The second law we learned in our gas laws unit was Charles' Law. In his law, he tells us that temperature and volume vary directly with each other. If the temperature increases in a gas, the volume will have to increase in order to keep the pressure constant because of the energized molecules. Here is a chart that exemplifies this:

http://agaul01.blogspot.com/2014/04/boyles-charles-law-in-relation-to.html

Here is his formula too. It is easy to plug in the information you get from a problem, but you have to make sure that you convert Celsius to Kelvin if the problem gives you a temperature in Celsius. :

https://www.clippard.com/cms/wiki/charless-law

Below are a couple links that explain Charles' law more and provide some practice math questions:

Chemteam

Practice Problems

First Lesson

Today in Chemistry, we learned our first Gas Laws Lesson. We focused on Boyle's Law, which only manipulates volume and pressure. It is an inverse relationship, and holds true at a constant temperature. Below is the formula:

http://www.physbot.co.uk/gas-laws.html

To represent its inverse relationship, take the picture below into account:

http://www.cyberphysics.co.uk/topics/kinetic_theory/boyle.htm

As you can see, as the volume decreases, the pressure increases, representing its inverse relationship.

Here are some more links that elaborate on Boyle's Gas Rule:

NASA

ChemTeam

Practice