1. STAAR Ladder to Success Rung 4

2. Boyle’s Law The pressure and volume of a gas are inversely related – at constant mass & temp P 1 V 1 = P 2 V 2

3. Charles’ Law The volume and absolute temperature (K) of a gas are directly related – at constant mass & pressure V 1 T 2 = V 2 T 1

4. Dalton’s Law The total pressure of a mixture of gases equals the sum of the partial pressures of the individual gases. P total = P 1 + P 2 +...

5. Avogadro’s Principle Equal volumes of gases contain equal numbers of moles – at constant temp & pressure – true for any gas 1 mol = 22.4 L

6. Ideal Gas Law PV=nRT You don’t need to memorize these values!

7. STP Standard Temperature & Pressure 0°C 273 K 1 atm101.325 kPa -OR- STP

8. Example #1 The pressure on a balloon with a volume of 300 mL increases from 1.10 to 2.00 atm. Calculate the new volume of the balloon.

9. Example #2 The air in a balloon with a volume of 25 L is heated from 20  C to 60  C. If the pressure stays the same, what will be the new volume of the balloon?

10. Example #3 A sample of gas in a 1L flask at 1.5 atm contains 75% CO 2 and 25% H 2 O gas. Calculate the partial pressures of each gas.

11. Example #4 Calculate the temperaure of 5.85 mol N 2 gas in a 12 L steel bottle under 10 atm of pressure.

12. Gas Stoichiometry Moles  Liters of a Gas: Moles  Liters of a Gas: – STP - use 22.4 L/mol – Non-STP - use ideal gas law Non- STP Non- STP – Given liters of gas? start with ideal gas law – Looking for liters of gas? start with stoichiometry conv.

13. Example #1 What is the mass of oxygen gas produced when 29.2 g of water is decomposed by electrolysis according to the balanced equation? 2H 2 O  2H 2 + O 2

14. Example #2 What volume in L of nitrogen dioxide gas is produced when 34 L of oxygen gas react with an excess of nitrogen monoxide? Assume conditions of STP. 2NO + O 2  2NO 2

15. Kinetic Molecular Theory Gases are made of molecules in constant, random motion The volume is small Collisions are elastic Forces (attractive and repulsive) are small Average kinetic energy is proportional to temperature