Gas Laws

First, Definitions

Directly proportional both variables will either increase or decrease

together

Inversely proportional one variable will increase and the other

variable will decrease

Do you have these definitions on your unit plan?

Temperature held constant?

What happens if the temperature is held constant?

As the volume decreases, what happens to the pressure?

It increases

Directly or Inversely Proportional?

Inversely

Pressure held constant?

What happens when the pressure is held constant?

As the volume decreases, what happens to the temperature?

It decreases

Directly or Inversely Proportional?

Directly

Volume held constant?

What happens when the volume is held constant?

As the temperature increases, what happens to the pressure?It increases

Directly or Inversely Proportional?

Directly

Boyle’s Law

Robert Boyle Studied relationship between

pressure and volume when temperature was constant

Determined

they were

inversely

proportional

Charles’ Law

Jacques Charles Studied relationship between volume and

temperature when pressure is held constant Determined they were directly proportional

Gay-Lussac’s Law

Joseph Gay-Lussac Studied relationship between

pressure and temperature when volume is held constant

Determined

they were

directly

proportional

Ideal vs. Real Gas

Ideal gases are gases whose particles take up no space and have no intermolecular attractive forces

Can you give an example of an ideal gas?Probably not….they do not exist in the

real world!Expressed by the question PV = nRT

Do you have these definitions on your unit plan?

Ideal vs. Real Gas

Real gases are gases whose particles take up space and have intermolecular attractive forces

Do you have these definitions on your unit plan?