GC1 Gas Laws (Charle's, Boyle's, Avogadro's, Ideal, and Combination)

Gas Laws (Charle's, Boyle's, Avogadro's, Ideal, and Combination)

1. GENERAL CHEMISTRY 1 Laws of Gas Properties

2. Laws of Gas Properties There are 4 general laws that relate the 4 basic characteristic properties of gases to each other. Each law is titled by its discoverer.

3. Pressure Pressure is defined as force applied per unit area. Mathematically it is given by, P=F/A. where F is the force acting perpendicular to the surface area A.

4. Atmospheric Pressure Also known as air pressure or barometric pressure (after the barometer), is the pressure within the atmosphere of Earth.

5. Pressure 1atm = 760mmHg = 760torr =101.3kPa = 14.7psi

6. Laws of Gas Properties There are 4 general laws that relate the 4 basic characteristic properties of gases to each other. Each law is titled by its discoverer.

7. Laws of Gas Properties Charles' Law Boyle's Law Avogadro's Law Gay Lussac's Law Ideal Gas Law (BCA) Combined Gas Law

8. Charles' Law This gives the relationship between volume and temperature if the pressure and the amount of gas are held constant

9. Charles' Law If the Kelvin temperature of a gas is increased, the volume of the gas increases. If the Kelvin temperature of a gas is decreased, the volume of the gas decreases.

10. Charles' Law This means that the volume of a gas is directly proportional to its Kelvin temperature. Think of it this way, if you increase the volume of a gas and must keep the pressure constant the only way to achieve this is for the temperature of the gas to increase as well.

11. Charles' Law Formula:

12. Boyle's Law This states that the volume of a given amount of gas held at constant temperature varies inversely with the applied pressure when the temperature and mass are constant.

13. Boyle's Law The reduction in the volume of the gas means that the molecules are striking the walls more often increasing the pressure, and conversely if the volume increases the distance the molecules must travel to strike the walls increases and they hit the walls less often thus decreasing the pressure.

14. Boyle's Law Like Charles' Law, Boyle's Law can be used to determine the current pressure or volume of a gas so long as the initial states and one of the changes

15. Boyle's Law Formula:

16. Avogadro's Law Gives the relationship between volume and amount of gas in moles when pressure and temperature are held constant.

17. Avogadro's Law If the amount of gas in a container is increased, the volume increases. If the amount of gas in a container is decreased, the volume decreases. This is assuming of course that the container has expandible walls.

18. Avogadro's Law Formula:

19. Gay Lussac's Law This states that the pressure of a given amount of gas held at constant volume is directly proportional to the Kelvin temperature.

20. Gay Lussac's Law If you heat a gas you give the molecules more energy so they move faster. This means more impacts on the walls of the container and an increase in the pressure. Conversely if you cool the molecules down they will slow and the pressure will be decreased.

21. Gay Lussac's Law Formula:

22. Ideal Gas Law A combination of the laws presented previously generates the Ideal Gas Law

23. Ideal Gas Law Formula: R = 0.0821 (L • atm/ mol • K)

24. Combined Gas Law The combined gas law allows you to derive any of the relationships needed by combining all of the changeable pieces in the ideal gas law: namely pressure, temperature and volume. R and the number of moles do not appear in the equation as they are generally constant and therefore cancel since they appear in equal amounts on both sides of the equation.

25. Combined Gas Law Formula: