Topic 5-Kinetic Theory And Gases

Question 1

What is the kinetic theory of liquids

Answer 1

Weaker forces of attraction 
Close together
Can't move past each other 
Irregular arrangement 
More energy than solids, move in random directions at slow speeds

Question 2

Kinetic theory of gases

Answer 2

Most have no forces of attraction
More energy than liquids or solids
Free to move in random directions at high speeds

Question 3

Why should Erin and Yas keep revising and going strong for they’re last day of revision

Answer 3

1) for they’re futures Dr Irwin and Dr Rivett
2) so they have no regrets over exams
3) so they can get on the A+ Paxton scheme (realistic Erin!!!)
4) so they can be the real life versions of Megan Hunt (aka Sass)

Question 4

The small particles of gas take up hardly any space, so most gas is…

Answer 4

Empty space

Question 5

What temperature is 0 kelvin in Celsius

Answer 5

-273

Question 6

What is the freezing point of water on the Kelvin scale

Answer 6

273K

Question 7

What is the boiling point of water on the Kelvin scale

Answer 7

373K

Question 8

What do you do to convert Celsius into kelvin

Answer 8

Add273

Question 9

What do you do to convert kelvin into Celsius

Answer 9

Subtract 273

Question 10

What is the kelvin temperature of gas directly proportional to

Answer 10

The average kinetic energy of its particles

Question 11

What happens when gas particles collide in a sealed container

Answer 11

They exert as force as they are light but not massless

In a sealed container they smash against walls causing outward pressure

Question 12

What does the outwards pressure of gas particles depend on

Answer 12

How fast the particles are going and how often they hit the walls

Question 13

When a gas is at constant pressure what is the pressure and volume proportional to

Answer 13

Temperature

Question 14

When the temperature of gas is at constant what does reducing the volume do

Answer 14

Particles get more squished and hit walls more often and pressure increases

Question 15

Pressure and volume are

Answer 15

Inversely proportional

Question 16

What is the relationship between volume and pressure when a gas of fixed mass is at a constant temperature

Answer 16

V1P1=V2P2

Question 17

How does an investigation using a gas syringe show volume and temperature at constant pressure

Answer 17

Half fill with gas and seal with rubber bung
Heat up causing gas to expand pushing plunger outwards-volume of gas increase as temp increases
Pressure stays same as plunger free to move
Cool, gas contact and plunger pulled in

Question 18

How to use a gas syringe to show pressure and volume at a constant temperature

Answer 18

Attach gas syringe half filled with air to pressure sensor
Push plunger on, compress gas and reduce volume
Increasing gas pressure (more collisions with walls)
Pull plunger out, increase volume and decrease pressure

Question 19

Why are gases used for medicine kept under high pressure and how

Answer 19

Have valve to adjust flow rate
Pressure inside must be higher than outside to ensure high flow rate (outside is 1atm) if equal wouldn’t empty completely flow rate would remain zero and gas would stay inside canister
High pressure means lots of gas stored in small volume

Question 20

Why do canisters holding gas need to be strong and give examples of materials

Answer 20

To hold the gas at high pressures without buckling or splitting
(Steel, carbon reinforced aluminium)
Size materials and pressures depend on what are where used for

Question 21

What is flow rate of gas

Answer 21

The volume of gas per unit time released from a gas bottle

Question 22

What is the kinetic theory of solids

Answer 22

Strong forces of attraction between particles, close together and fixed in regular arrangement
Not much energy, vibrate in fixed positions