1. Ch. 10: Physical Properties of Gases
10.3 Gas Laws:
Relationships between volume, temperature, pressure, and amount of gas.

2. Boyle’s Law: P and V as one increases, the other decreases
inversely proportional
pressure is caused by moving molecules hitting container walls

3. Boyle’s Law: P and V
Boyle’s Law: the V of fixed mass of gas varies inversely with P at a constant T.
What kind of graph is V vs. P?

4. Boyle’s Law

5. Example: Boyle’s Law
Consider a 1.53-L sample of gaseous SO2 at a pressure of 5.6 x 103 Pa. If the pressure is changed to 1.5 x 104 Pa at constant temperature, what will be the new volume of the gas?

6. Charles’ Law: V and T if P is constant, gases expand when heated
when T increases, gas molecules move faster and collide with the walls more often and with greater force
to keep the P constant, the V must increase

7. Charles’ Law: V and T
Problem: if we use Celsius, we could end up with negative values from calculations in gas laws for volumes
we need a T system with no negative values: Kelvin Temperature Scale
starts at ° C = absolute zero = 0 K
lowest possible temperature

8. Charles’ Law: V and T
Charles’ Law: the V of fixed mass of gas at constant P varies directly with Kelvin T.
What kind of graph is V vs. T?

9. Charles’ Law discovered by French physicist, Jacques Charles in 1787
first person to fill balloon with hydrogen gas and make solo balloon flight

10. Example: Charles’ Law
A sample of gas at 15°C and 1 atm has a volume of 2.58 L. What volume will this gas occupy at 38°C and 1 atm?