Bell Work: Gasses List 10 things you know about gases. . . anything you can think of related to a gas.

Gas Laws

Remember: P = Pressure: force/area Units: Pa, kPa, atm, torr, mmHg, N/m2 V = Volume: space an object takes up Units: L, mL, m3, cm3, dm3 T = Temperature: measure of kinetic energy Units: K, C

There are LOTS of gas laws with formulas. When solving gas law problems, to pick the correct formula you must look at the variables changing AND what is held constant!

Boyle’s Law pressure vs. volume Volume is inversely proportional to pressure. This means if one goes up, the other goes down. V P

Boyle’s Law Formula: demo P1V1 = P2V2

Boyle’s Law Graph

Charles’ Law volume vs. temperature Volume is directly proportional to it’s Kelvin temperature. This means if one goes up, so does the other. V T

Charles Law formula demo V1 = V2 T1 T2

Kelvin Temperature must be in Kelvin. 0 on the Kelvin scale is known as absolute zero. Absolute zero is the lowest temperature that can exist. At absolute zero: kinetic energy = zero

How is Kelvin temperature found from Celsius temperature? K = °C + 273 Write on your paper: Practice: Convert 20°C to Kelvin 20°C + 273 = 293 K

What is the Celsius temperature of absolute zero? K = °C + 273 0 K = x + 273 -273°C = x

Charles’ Law Graph

Combined Gas Law formula: P1V1 = P2V2 T1 T2 Make sure to use the Kelvin temperature and cross-multiply to solve these problems!

Combined Gas Law involves pressure, volume, and temperature combines Boyle’s Law and Charles’ Law