1. REVIEW HOMEWORK ?? What is the formula for Avogadro’s Law? What happens to volume when the number of moles increases? Avogadro’s Law Questions 1-4

2. REVIEW HOMEWORK ?? What is the formula for Boyles Law? What happens to volume when pressure increases? Boyle’s Law Questions 1-8

3. Charles’ Law Jacques Charles 1746 – 1823 1746 – 1823

4. Charles’ Law At constant pressure, the volume of a gas varies directly with its Kelvin temperature Equation: V1 V2 = T1 T2 Volume = L Temperature = K

5. Charles’ Law Cross multiply the equation: V2V2 = T1T1 T2T2 V1V1 Resulting Equation: V 1 T 2 = V 2 T 1

6. At Constant Pressure, V  T  means proportional When volume, temp Temp. scale K not °C What error exists on this graph?

7. Solving Charles’ Law Problems –Write the given information –Determine an equation to use –Isolate the missing variable –Convert to Kelvin temp. scale –Plug-in the given values and solve

8. Write Given Info. A volume of 20.0m 3 of argon gas is kept under constant pressure. The gas is heated from 22ºC to 283 ºC. What is the new volume of the gas? V 1 = 20.0 m 3 T 1 = 22ºC T 2 = 283 º C V 2 = ?

9. Determine an Equation & Isolate V 2 V 1 T 2 = V 2 T 1 T1T1 T1T1 V1T2V1T2 T1T1 = V 2

10. Temperature Conversion Equations Celsius to Kelvin K = ºC + 273 Fahrenheit to Celsius ºC = 5/9 (º F – 32)

11. Convert ºC to K Given Info. V 1 = 20.0 m 3 T 1 = 22ºC T 2 = 283 º C V 2 = ? K = ºC + 273 K = 22 + 273 K = 295 K = ºC + 273 K = 283 + 273 K = 556

12. Plug-in Given Values and Solve Given Info. V 1 = 20.0 m 3 T 1 = 295K T 2 = 556K V 2 = ? V1T2V1T2 T1T1 = V 2 (20.0 m 3 )(556K) = V 2 295K 37.7 m 3 = V 2

13. Turn to a person next to you… “I’m here to help whenever I can”

14. Outstanding Teamwork! Let’s try a few more Charles’ Law problems.

15. EXERCISE