1. Sabreena, Olivia Jahari, Cindy
Combined Law
Sabreena, Olivia
Jahari, Cindy

2. Definition/Description
The combined law is a combination of Charles’ Law, Boyle’s Law and Gay- Lussac’s Law.
It states the ratio between the product of the pressure and volume and the constant temperature of the system.

3. Equation P1V1 = P2V2 _________________
T1 T2 *if there’s two different conditions in the problem

4. Examples A car engine Shooting a gun
Tires of a car-gas remains constant but the pressure increases.
Spray cans-releases pressure causing the gas to expand in the bottle.
Scuba diving- as the pressure increases the temperature decreases and the volume depends on the factors of the other two.

5. Pictures and graphs

6. Video
Stop at 4:14.

7. How to solve a problem that has different conditions
Step 1: write out boyles law: p1v1=p2v2
Step 2: multiply by charles law:p1v1^2/t1=p2v2^2/t2
Step 3: multiply by gay lussacs:p162v1^2/t1^2=p2^2v2^2/t2^2
Step 4 : take square root to get combined law:p1v1/t1=p2v2/t2

8. Example problems
A sample of sulfur dioxide occupies a volume of 652 mL at 40.° C and 720 mm Hg. What volume will the sulfur dioxide occupy at STP if the final pressure is at 760?
A sample of nitrogen gas occupies a volume of 2.00 L at 756 mm Hg and 0.00° C. The volume increases by 4.00 L and the temperature decreases to 137 K. What is the final pressure exerted on the gas?

9. Answers to the Problems
P1 = 720 mm P2 = 760 mm V1 = 652 mL V2 = ? T1 = 40.° C = 313 K T2 = 0° C = 273 K = 540 mL SO24

10. Answer to the Problems
P1 = 756 mm P2 = ? V1 = 2.00 L V2 = 4.00 L T1 = 0.0° C = 273 K T2 = 137 K = 191. mm Hg