Ch15 ideal gases

Question 1

mole

Answer 1

1 mole of a substance contain 6.02x10^23 particles

Question 2

moles equations

Answer 2

number of moles = mass/molar mass
number of particles = Na x number of moles

Question 3

Assumption of the model of kinetic theory of gasses

Answer 3

• Large numbers of particles in random rapid motion.
• volume of individual particle is negligible compared to the volume of gas.
• all collisions are perfectly elastic, time spent in collisions in negligible compared to time spent between collisions.
• no forces exerted between particles unless in collisions

Question 4

Ideal gas equations

Answer 4

PV=nRT
n= NO of moles
R= gas constant
T= temperature in kelvin

PV=NKT
N= NO of particles
K= boltzman constant
T= temperature in kelvin

Question 5

Boltzmann constant

Answer 5

pv=nRT pv=NKT
nRT=NKT
nR=NK
K=nR/N N=nxNA

K=nR/nxNA
K=R/NA

Question 6

Boyles law

Answer 6

PV = nRT
where T=constant
R=constant
n=constant
PV=constant
P=1/V
P1V1=P2V2

Question 7

Boyles law experiment.
procedure and evaluation:

Answer 7

• step on the foot pump to increase pressure
• measure the volume for different values of pressure
• plot a graph of p against 1/v
• if the graph shows a relationship of p being proportional to 1/v, Boyles’s law is proved.

Question 8

pressure law

Answer 8

PV=nRT
V=constant
R=constant
n=constant
P=nR/V x T p=constant x T
P/T = constant P1/T1=P2/T2

Question 8

Pressure law experiment:

Answer 8

• submerge a flask with a fixed volume in a water bath.
• heat the water bath using a Bunsen burner, vary temperature then measure temperature and pressure.
• plot a graph of P against T.
  -draw a line of best fit and extrapolate to find absolute zero.