Gas Laws

Question 0

Kinetic Theory of Gases

Answer 0

1) The molecules/atoms that make up a gas have virtually no volume compared to the volume that the gas occupies. (This volume is due to motion of the gas molecules)
2) This motion is constant & random. (direction & speed)
3) All collisions between molecules are perfectly elastic (no loss of motion to other forms of energy).

Question 1

Gas Laws

Answer 1

Mathematical relationships that describe properties of gases.

Question 2

Pressure (P)

Answer 2

Force #of collisions
–––––
Area surface area of container

collisions { # particles present

Question 3

Atmospheric (Atm) Pressure

Answer 3

Collisions from atmospheric gases with the dish of Hg. (Measured by height of Hg)

Question 4

Standard Pressure (sea level)

Answer 4

760 mmHg
29.92 inHg
1 Atm
101.3 kPa

Question 5

Water Pressure

Answer 5

10m of water = 1 Atm

Question 6

Boules Law (1662)

Answer 6

For a fixed mass of gas at constant temp, the pressure & volume of the gas varies indirectly.
P1V1 = P2V2

Question 7

Charles’ Law (1787)

Answer 7

For a fixed mass of gas at constant pressure, the Kelvin temp & volume of the gas varies directly.
V1 V2
–– = ––
T1 T2

Question 8

Amonton Guy-Lussac’s Law (1802)

Answer 8

For a fixed mass of gas at constant volume, the Kelvin temp & pressure very directly.
P1 P2
–– = ––
T1 T2

Question 9

Maldenburg Spheres

Answer 9

The particles of the atm colliding w/ the sphere on the outside & very few collisions on the inside, so the atm pushes the sphere together.
At same pressure: easy to separate b/c the collisions inside = collisions outside.

Question 10

The Combined Gas Law

• Sealed Container
• Kelvin Temp.

Answer 10

P1V1 P2V2
––––– = –––––
T1 T2

Question 11

Dalton’s Law of Partial Pressure

Answer 11

The total pressure for a mixture of gases is the sum of the individual pressures at the same conditions (vol & temp).
Σ IndPressure = Σ TotalPressure

Question 12

Gas over Water (Wet Gas)

Answer 12

PAtmOutside = PDryGas + PH2OVapor

Question 13

Ideal Gas Law

Answer 13

PV=nRT
R is universal gas constant 
8.21Atm
8.31kPa
6.24mmHg

Question 14

Graham’s Law of Diffusion

Answer 14

The movement of gases/liquid/ions (solute) from areas of high concentration toward areas of low concentration until there is a uniform concentration throughout.
-Driven by Random Molecular Motion
RateA     √M. Mass B
–––––  =  –––––––––––
RateB     √M. Mass A