The Gas Laws

1. The Gas Laws And what they can do for me! =D

2. Put Simply. The gas laws are a series of rules and equations used to determine how a gas will react to various changes in its established situation.

3. Put simply-er These are the rules used to tell what will happen to a gas when stuff happens.

4. Here is what will be covered… • Boyle’s law for pressure. • Charle’s law for temperature. • Gay Lussac’s law of temperature. • Combined gas law. • Ideal gas law. • Avogadro’s hypothesis. • Dalton’s law of partial pressure. • Graham’s law of effusion.

5. Boyle’s law for pressure • For a given mass of gas at a constant temperature the volume varies inversely with pressure • P1 x V1 = P2 x V2

6. Boyle’s law for pressure Pressure=200kPa Volume=0.5 L Pressure=100kPa Volume=1.0 L Pressure=50kPa Volume= 2.0 L

7. Boyle’s law for pressure

8. According to Boyle’s law… • If pressure doubles volume will do what? • If volume quadruples then pressure is divided by? Volume will be divided in half. 4

9. Charles’ law for Temperature • The Volume of a fixed mass of gas is directly proportional to its Kelvin temperature if the pressure is kept constant. • V1 / T1 = V2 / T2

10. Charles’ law for Temperature Pressure=100 kPa Volume=20 L Temperature=200 K Pressure=100 kPa Volume=5 L Temperature=50 K Pressure=100 kPa Volume=10 L Temperature=100 K

11. Charles’ law for Temperature

12. According to Charles’ law • If temperature is doubled then volume does what? • If Volume triples then pressure does what? Volume doubles PSYCH! Nothing.

13. Gay-Lussac’s law of temperature • The pressure of a gas is directly proportional to the Kelvin temperature if the volume remains constant. • P1 / T1 = P2 / T2

14. Gay-Lussac’s law of temperature Pressure=200 kPa Pressure=50 Pressure=100 kPa Volume=10 L Volume=10 L Volume=10 L Temperature=400 K Temperature=100 K Temperature=200 K

15. According to Gay Lussac’s law… • If pressure triples then temperature does what? • If the temperature stays constant can the pressure go up? Temperature triples Hell naw it can’t

16. Combined gas law • A combination of Gay-Lussac’s law, Charles’ law & Boyle’s law. • No need to remember all 3 separately. • (P1 x V1)/T1 = (P2 x V2)/T2 • Any part can be canceled out to make the other laws

17. Ideal gas law. • Adds fourth variable to Combined gas law. • Moles (n), take in to account the size of gas particles. • (P1 x V1)/(T1 x n1) = (P2 x V2 )/(T2 x n2)

18. Ideal gas law questions • !Double worth! • Show how you can make the ideal gas law equation turn in to any of the preceding equations.

19. Avogadro’s Hypothesis • Equal volumes of gases at the same temperature and pressure contain equal numbers of particles.

20. Avogadro’s Hypothesis Pressure, temperature, and volume is same for both.

21. Avogadro’s hypotheses questions • What is Avogadro’s hypothesis? • How many particles were shown on the last fame? Equal volumes of gases at the same temperature and pressure contain equal numbers of particles. 32

22. Graham’s law of effusion • The rate of effusion for a gas is inversely proportionate to the square root of the gases molar mass. • Diffusion= the tendency of molecules to move towards areas of lower concentration until equilibrium is reached. • Effusion= gas escaping through a tiny hole. • Rate A = sqr root of molar mass B Rate Bsqr root of molar mass A

23. Diffusion Effusion

24. Graham’s law questions • What is diffusion? • What is effusion • A gas’s rate of effusion is ________ proportionate to its __________. the tendency of molecules to move towards areas of lower concentration until equilibrium is reached. gas escaping through a tiny hole. Inversely Molar mass

25. K.THNX.CLAP.