The Ideal Gas Law

1
The Ideal Gas Law

• Chemistry

2
The Ideal Gas Law

• The Ideal Gas Law combines the properties of
  volume, pressure, and temperature, to predict the
  number of particles (moles) in a sample.
• This can be represented by the equation
• PV nRT

3
Whats This R Business?

• R is called the Universal Gas Constant. It will
  always be the same for every problem you do with
  PVnRT. Lets find its value using what we know
  about STP.
• What is STP (Standard Temperature Pressure)?
• and how much space does 1 mol of gas take-up at
  STP?

4
Calculating R

• So we said STP 0C, 1 atm
• 22.4L 1 mol of gas _at_ STP
• P
• V
• n
• T
• R ?

5
Using PVnRT

• When given a PVnRT problem, you will be given
  one unknown, and the other four values will be
  known. Arrange the equation to solve for that
  value.

6
Practice

• You have a basketball filled with air. You know
  the following
• P 1.1 atm
• V 8.5 L
• n ???
• R 0.082 Latm/Kmol
• T 298K
• How many mol of gas are in the basketball?

7
Practice

• 20 mol of gas occupy 14L of space at 273K. What
  is the pressure of the gas?
• P V
• n R
• T

8
Practice

• If we have 45.6g of Chlorine gas in a balloon at
  STP, what is the volume of the balloon?