1. Moles and Gases

2. Achievement Indicators  Determine relationships between molar quantities of gases at STP  define STP and state the molar volume of a gas at STP (i.e., 22.4 L/mol)  determine experimentally the molar volume of a gas at room temperature and pressure  calculate the moles or mass of a gas from a given volume at STP or vice versa

3. Gases and Moles  The volume occupied by a certain amount of gas depends on the temperature and pressure

4. Standard Temperature and Pressure (STP)  Standard Temperature 0°C (273 K)  Standard Pressure 101.3 KPa (1 atmosphere)

5.  The volume of one mole of any gas @ STP is… 22.4 L

6. The Molar Volume @ STP is Only For Gases at STP

7. Flowchart Moles Litres at STP Divide by 22.4L mol Multiply by 22.4 L mol

8. Calculations 1. Find the volume occupied by 0.600 moles of CO 2 at STP. 0.600mol x = 13.4 L

9. Calculations 2. Find the number of moles in 264.0 mL sample of NO 2 at STP. 264.0 mL x x = 1.18 x 10 -2 mol

10. Homework  p. 83  # 11 & 12

11. x (1mol / ?g) x (?g / 1mol) x (1mol / 22.4L) x (22.4L / 1 mol) Volume at STP Mass (g) 1 MOLE

12. Calculations  Find the volume occupied by 22.0 g of CO 2(g ) at STP  Plan: g  mol  L 22.0 g CO 2 x x = 11.2 L

13. Now You Try a) Find the mass of a 200.0 mL sample of NO 2 (g) at STP.  Plan mL  L  mol  g 200.0 mL x x x = 0.411g

14. b) Find the volume occupied by 3.60 Kg of fluorine at STP. Kg  g  mol  L 3.60 Kg x x x = 2.12 x 10 3 L

15. Homework p. 83 #11 & 12 p. 86 & 87 # 22 (b & i) #24 (a,c,e,g)