1. More Intro to Gases
Chemistry GT

2. Drill
Convert:
1.4 atm to mmHg
95.5 kPa to atm
16.0 lb/in2 to kPa
754.3 mmHg to lb/in2
HW: Finish Boyle’s and Charles’ Law lab questions and graphing

3. Objectives IWBAT Describe gases by their properties
Discover the mathematical relationships in Boyle’s and Charles’ Law.
Use the Combined Gas Law.

4. Date Announcements Tuesday 4/21
AM (B207) or PM (N211) – come for make-up tests/quizzes
Wednesday 4/22 – NO Lion’s Time, SMOB and SGA elections
Thursday 4/23 – PBIS (no, I don’t have a schedule)
Friday 4/24 – Fandemonium Society Meeting in N211 

5. Agenda Drill Finish the Properties of Gases
Charles’ and Boyle’s Law Online Lab & graphing
Combined Gas Law Notes & Practice Problem
Closure

6. Physical Properties of Gases
Expansion -- no definite shape or volume
Fluidity -- flows freely
Low density
Compressibility -- may be crowded together
Diffusion -- spontaneous mixing of two gases
Effusion -- particles under pressure can leak out of a tiny opening
Standard Temperature and Pressure (STP): 1 atm, 273K

7. Boyle’s Law Online Lab Groups of 3 or 4
Go to msbloedorn.weebly.com > Chemistry > Unit 11: Gases > Charles’ Law Online Lab, Boyle’s Law Online Lab
Record your data. When done, get a sheet of graph paper and graph all data on the same graph—Boyle’s Law. Charles’ Law on separate graph.
Once everyone has data, we will move to the notes.

8. The Combined Gas Law The Combined Gas Law:
P1V1 = P2 V2
T T2
Take an index card. Write PTV in large letters that fill the card. You may hole-punch the card or just draw large dots at the bottom.
What happens when you hold one constant??
Example problem—Combined Gas Law WS

9. Exit Ticket
A balloon contains 3.5 L of air at 4.0 atm of pressure. The balloon pops, letting the air out. The air is now at 1.0 atm. To what volume will it expand?