Gas Laws

Question 1

Boyle’s Law

Answer 1

for a fixed mass of gas at a constant temperature
as volume increases, pressure decreases
gives a curved graph - inversely proportional
for a straight line graph, P = kV
where k is a constant
PV is constant

Question 2

Boyle’s Law Equation

Answer 2

P1V1 = P2V2

Question 3

Charles’ Law

Answer 3

for a fixed mass of gas at a constant temperature
volume is directly proportional to temperature, T if T is in Kelvins
volume is proportional to temperature is T is in degrees Celsius
relationship crosses the x axis at -273 degrees C
V/T is constant

Question 4

Gay-Lussac’s Law

Answer 4

for a fixed mass at a constant volume
pressure is directly proportional to temperature if T measured in Kelvins
P/T is constant

Question 5

Charles’ Law equation

Answer 5

V1 / V2 = V2 / T2

Question 6

Gay-Lussac’s Law equation

Answer 6

P1 / T1 = P2 / T2

Question 7

Gas Equation

Answer 7

PV/ / T = a constant
P1 V1 / T1 = P2 V2 / T2 -> just scrap whichever one's constant in the question
PV = NKT
where: PV = constant x T
N = no. of molecules
T = temperature (K)
K = Boltzman constant (1.38 x 10 ^ -23)

Question 8

Explain how Charles’ Law and Gay-Lussac’s Law (pressure-temperature) lead to the concept of absolute 0

Answer 8

1. Charles’ Law = for a fixed mass at a constant pressure volume is proportional to temperature
2. Gay-Lussac’s Law = for a fixed mass at a constant volume, pressure is proportional to temperature
3. the relationship between P & T and V & T is not directly proportional because it doesn’t go through zero
4. if we extrapolate backwards from these graphs, it cuts the x - axis at -273 degrees C
5. this is absolute zero, when particles have absolutely no energy
6. Sketch graphs of Charles’ and GL’s Laws