S1.5 (Ideal Gases)

Question 1

Boyle’s Law

Answer 1

At constant temperature, pressure and volume of a fixed ideal gas are inversely proportional to eachother

Question 2

Charles Law

Answer 2

At constant pressure, volume and temperature of a fixed gas are directly proportional

Question 3

Avogadros Law

Answer 3

Under standard conditions of 100kPa and 273K, the volume 1 mole of gas is 22.7dm3

Question 4

Why is it Ideal gas law

Answer 4

• at low molar mass; particles can move faster meaning IMF are weaker

Question 5

Gay Lussacs Law

Answer 5

At constant volume, pressure of a fixed mass of an ideal gas is directly proportional to its absolute temperature in Kelvin

Question 6

Why is it Real Gas

Answer 6

• at high molar mass, particles move slower therefore IMf are stronger and can have effect

Question 7

Assumptions of ideal gas model

Answer 7

1. Particles in a gas are in constant, random, straight line motion
2. negligible IMF’s between particles
3. collisions between particles and container walls are elastic (no energy lost)
4. gas particles have negligible volume (Distance between particles is so large it doesn’t matter)
5. Avg. Ekin is directly proportional to absolute temperature in kelvin

Question 8

Real gases

Answer 8

Gases that deviate from the idela gas law behaviour to some extent
(as long as there are IMF’s = gas is real)

Question 9

Ideal gas Law

At low pressure..

Answer 9

gases act as ideal gases
* particles are far apart
* IMF’s negligible

Question 10

At high pressure

Answer 10

gases are real
* particles are close together
* IMF’s can have effect

Question 11

At low temperature…

Answer 11

gases are real
* particles have low avg Ekin
* IMF’s can have effect

Question 12

At high temperature…

Answer 12

gases are ideal
* particles have higher Ekin
* IMF’s have no effect

Question 13

Ideal gas conditions

Answer 13

• high temperature
• low pressure (because this assumes big volume)

Question 14

Real gas conditions

Answer 14

• low temperature
• high pressure

Question 15

How do particles move in ideal gases

Answer 15

randomly in straight line motion

Question 16

How to remember charles law

Answer 16

Charles, Pressure, what pressure? (constant, unaffacted)
As temp up, volume up

Question 17

which scenario is not a straight lined graph

Answer 17

volume against pressure at constant temperature

Question 18

how do ideal gases move

Answer 18

constant, random, straight lined motion

Question 19

properties of ideal gases

Answer 19

• constant, random, straight-line motion.
• negligible IMF’s
• Collisions between particles or with the walls of the container are perfectly elastic (no energy is lost).
  *distance between the particles is much greater than the size of the particles = negligible volume.
  *average kinetic energy of the particles in a gas is directly proportional to the absolute temperature (in kelvin)