chapter 15

Question 1

Assumptions for the kinetic theory of gases

Answer 1

large number of molecules in a random motion with a random speed

volume occupied by particles is negligible compared to the volume occupied by the gas

collisions are perfectly elastic and time of collisions is negligible compared to time between collisions

Negligible forces between particles except during collisions

Question 2

Boyle’s law explained

Answer 2

When mass and temperature are constant:
pV = constant
p is proportional to 1/v

Question 3

Investigate Boyle’s law

Answer 3

A sealed syringe with gas is connected to a pressure gauge
change the volume to not change the temperature by producing friction
slowly and plot p against v

Question 4

Charles Law

Answer 4

When mass and volume are constant:
p/T = constant
p is proportional to T

Question 5

Investigate absolute 0 using Charle’s law

Answer 5

Connect a sealed flask to a pressure gauge
place in a water bath and vary the temperature
you can plot p against temperature in Celsius from x >= 0
extrapolate the straight line to y = 0

Question 6

all forms of pV

Answer 6

pV - nRT
pV = NKT
pV = 1/3 x Nm C^{^2}
p₁V₁ = P₂ V P₂ / TP₂ x T₁

Question 7

Deriving the equation shows that the average kinetic energy of the molecules is proportional to the temperature

Answer 7

1/3 Nmc^2 = NKT
cancel N factor out 2/3
1/2 m c ^ 2 = 3/2 KT
Kinetic energy = 1.5 times the boltzmann constant times the temperature

Question 8

The internal energy of an ideal gas

Answer 8

The internal energy of an ideal gas is equal to the kinetic energy as the electrostatic potential was assumed to be negligible except during collisions