Chemistry- Unit 6

What factor effects pressure

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

Amount of gas (n)

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

Volume of container (V)

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

• Temperature (T)

– ↑T, more KE, more collision; ↑ P

SI Unit for pressure

kPa (kilopascal)

STP of pressure

1 atm

1 atm = blank kPa

101.325 kPa

1 atm= blank mm Hg

760 mm Hg

1 atm= blank torr

760 torr

What is torr named after?

named after the Torricelli (inventor of
barometer)

Choose the correct answer:

Which one is Boyle’s law?

a. P1V1=P2V2

b. V1/T1=V2/T2

c. P1T1=P2T2

a. P1V1=P2V2

What does Boyle’s law state about the relationship between P and V?

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

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

What is Charles’s Law?

V1/T1=V2/T2

What does Charlies’s law state about the relationship between T and V?

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

T must be in blank for Charles Law

Kelvin

What is Gay-Luccas Law?

P1/T1=P2/T2

What does Gay Luccas Law state about the relationship between P and T?

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

What is the combined gas law?

P1V1/T1 = P2V2/T2

What does the combined gas law state about the relationship between P, V and T

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

What is Avogardos Hypothesis?

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

What is the formula for Avogardos Hypothesis

V1/n1=V2/n2

What is the relationship between V and n for Avogardos Hypothesis?

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

What is the Ideal Gas Law?

Combines all the gas laws

PV=nRT

What does the ideal gas law conform to?

Kinetic theory

What is R of kPa

8.314

What is R of mm Hg and torr

62.26

What is R of atm

0.0821

What is real gas?

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

Most gasses are considered ideal unless its at a blank and a blank

high pressure and a low temperature

What is Dalton’s Law of Partial Pressure?

• 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

What is Dalton’s Law of Partial Pressure? (formula)

– P total = Pa+ Pb+ ... + Pn

Graham’s Law of Diffusion

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

What is diffusion?

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

What is effusion?

gas escaping through a small hole in a container