Chemistry- Unit 6

Collision of molecules with the container wall
exerts pressure (more collision, more pressure)

– ↑ n, more collision between molecules and the
container wall; ↑ P

– ↑ V, more space for molecules to travel before hitting
the container wall; ↓ P

– ↑T, more KE, more collision; ↑ P

kPa (kilopascal)

1 atm

101.325 kPa

760 mm Hg

760 torr

named after the Torricelli (inventor of
barometer)

a. P1V1=P2V2

Relationship between P and V (T and n are
constant)

↑P, ↓ V (inversely proportional)
– PV = k (constant)

V1/T1=V2/T2

Relationship between T and V (P and n are
constant)
– ↑T, ↑ V = directly proportional
– V/T = k (constant)

Kelvin

P1/T1=P2/T2

Relationship between P and T (V and n are
constant)
– ↑P, ↑T – directly proportional
– P/T = k (constant)

P1V1/T1 = P2V2/T2

Relationship between P, T and V (n is
constant)
– PV = k
T

At same T and P, each volume of gas contains
equal amount (moles) of gas

V1/n1=V2/n2

Relationship between V and n (T and P are constant)
– ↑n, ↑V – directly proportional
– V/n = k (constant)

Combines all the gas laws

PV=nRT

Kinetic theory

8.314

62.26

0.0821

has attraction/repulsion between molecules and gas molecules take up certain amount of volume

high pressure and a low temperature

• The total pressure in a container is equal to
  the sum of all the partial pressure of each
  gas

• Container with more than 1 gas
  – Each gas exerts it’s own amount of pressure
  (partial pressure) (Pa

– P total = Pa+ Pb+ ... + Pn

Rate of diffusion of a gas is inversely
proportional to the √FM

movement of gas from a high concentration to a low concentration due to random movement of gas particles

gas escaping through a small hole in a container