Gases and Solutions

Question 1

Boyle’s Law

Answer 1

P₁V₁ = P₂V₂

P ∝ 1/V

P: pressure
V: volume

Question 2

Charles’ Law

Answer 2

V₁/V₂ =T₁/T₂

V∝T

T needs to be in K

Question 3

Avogadro’s Hypothesis

Answer 3

Equal vols of different gases collected under similar conditions have the same number of particles

V∝n

Question 4

Dalton’s Law of partial pressures

Answer 4

Total pressure = ∑partial pressures

Question 5

Combined gas law

Answer 5

(P₁V₁)/T₁ = (P₂V₂)/T₂

Question 6

Graham’s law of diffusion

Answer 6

r ∝ 1/√d

Diffusion rate is inversely proportional to the square root of the density

Comparative diffusion rate:
r₁/r₂ ∝ √d₂/d₁

Question 7

Raoult’s Law

Answer 7

Partial vapour pressure of a component in a mixture = vapour pressure of the pure component at that temp x it’s mole fraction within the mixture

Only works for ideal mixtures (same type of solutes)

Question 8

Raoult’s law equations

Answer 8

Pa = Xa x Pa•
Pb = Xb x Pb•

Pa and Pb = partial vapour pressures
Xa and Xb = a and b mole fractions
P• = vapour pressures of pure liquid forms

Total vapour pressure = Pa + Pb

Question 9

Boiling and vapour pressure

Answer 9

Higher vapour pressure = lower boiling point - molecules escape easier from the surface, therefore weaker intermolecular forces