Chapter 1

Question 1

Solids

Answer 1

• Closed together in fixed positions to form a regular lattice arrangement -> strong forces of attraction between particles
• Don’t move from their positions -> definite shape and volume
• Vibrate in the spot -> the hotter the solid becomes = partciles vibrate more (causing solids to expand slightly when heated

Question 2

Liquids

Answer 2

• Randomly arranged and free to move past each other but tend to stick closely together -> weak forces of attraction between particles
• Flow to fill container -> definite volume but jot shape
• Constantly moving in random motion -> the hotter the liquid gets= the faster the particles move (casuing liquids ro expand slightly when heated)

Question 3

Gasses

Answer 3

• Far apart and free to move travelling in straight lines -> very weak forces of attraction between particles
• Move to fill container -> no definite shape of volume
• Constanly moving with random motion -> the hotter the gas gets= particles move faster
  (gas either expand when heated OR pressure increases)

Question 4

liquid to solid

Answer 4

Freezing

Question 5

Solid to liquid

Answer 5

Melting

Question 6

Liquid to gas

Answer 6

Evaporating or boiling

Question 7

Gas to liquid

Answer 7

Condensing

Question 8

Gas to solid

Answer 8

Deposition

Question 9

Solid to gas

Answer 9

Sublimation

Question 10

Boiling

Answer 10

When liquid heated to its boiling point -> gradually turns into gas

Question 11

Evaporating

Answer 11

Can happen at any temperatures below a liquids boiling point -> more energetic particles near the surface of the liquid can escape to form a vapour

Question 12

Temperature during a change of state

Answer 12

It doesn’t change -> stays constant

Question 13

Heating

Answer 13

Energy put in absorbed to overcome forces between particles

Question 14

Cooling (condensing + freezing)

Answer 14

Thermal energy released from formation of new forces between particles stops temperature from falling

Question 15

Sloped bits (heating and cooling curves)

Answer 15

Temperature of substance increasing

Question 16

Flat bits (heating and cooling curves)

Answer 16

Substance changing state

Question 17

Volume of gasses: pressure

Answer 17

Increasing pressure: partciles pushed closer together -> volume decreases
Decreasing pressure: particles can drift further apart -> volume increases

Question 18

Volume of gasses: temperature

Answer 18

Increasing temperature: particles have more kinetic energy + move faster and so spread out and occupy more space -> volume increases
Decreasing temperature: particles have less kinetic energy + move less and don’t spread out -> volume decreases

Question 19

Diffusion

Answer 19

Net movement of particles from an area of high concentration to low concentration -> due to random movement of particles in liquids and gasses (no energy needed)

Question 20

Rate of diffusion of gas

Answer 20

Depends on its molecular mass -> small, light gas molecules move faster than longer, heavy gas particles and so will diffuse faster