2. Gas Laws

3. Units Used With Gas Laws PRESSURE: The force applied by many gas particles colliding with each other. 1.Atmospheres (atm) STP= 1atm 2.Pounds per square inch (PSI) STP= 14.7 3.Pascal (Pa) SI UNIT! STP= 101.3 kPa 4.Millimeters of Mercury (mm Hg) STP= 760 5.Torr (named after Torricelli) STP= 760 –Evangelista Torricelli invented the barometer which used mercury.

4. Units Used With Gas Laws 2 Temperature: 1.Celsius (°C) STP=0 2.Kelvin (K) STP=273 To convert °C to K: K=°C + 273 Example: 23°C =?K 23°C + 273= 296K

5. Units Used With Gas Laws 3 Volume: Volume can be measured in liters (L) or milliliters (mL).

6. 3 Major Gas Laws Boyle’s Law Charles’s Law Gay Lussac’s Law

7. Boyle’s Law Robert Boyle (1627- 1691) Born in Ireland, and died in England. 1 st person to do an actual study on how volume and pressure effect each other.

8. Boyle’s Law In all of Boyle’s studies, the temperature of the gas is always constant. Boyle came up with equation: P 1 *V 1 =P 2 *V 2 Boyle’s equation indicates an inverse relationship between pressure and volume. If the pressure goes up, than the volume must go down.  volume,  pressure

9. Boyle’s Law (P vs. V)

10. Charles’s Law Jacques Charles (1746-1823) He built the first large balloon. He studied the effects that temperature had on the volume of a gas.

11. Charles’s Law 2 In all of Charles’s studies, the pressure is always constant, and the temp. in always in Kelvin. Charles came up with the equation: V 1 /T 1 = V 2 /T 2 Charles’s equation indicates that there is a direct relationship between the temperature of a gas and it’s volume.  volume,  temp.  temp.,  volume

12. Charles’s Law (T vs. V)

13. Gay-Lussac’s Law Joseph Gay-Lussac (1778-1850) A French chemist who traveled over 7,000 meters in altitude in a hot air balloon. He studied the effects that temperature had on the pressure of gases.

14. Gay-Lussac’s Law 2 Lussac’s greatest discovery was the relationship between pressure and temperature. The volume for his problems will always be constant, and the temp. must be in Kelvin. Lussac’s equation: P 1 /T 1 = P 2 /T 2 This equation indicates that there is a direct relationship between pressure and temperature.  temp.,  pressure  pressure,  temp.

15. The Ideal Gas Law This gas law is used to determine the amount of gas, in moles, in a system. The equation is: PV=nRT n=the number of moles of a gas *