chapter 1: kinetic particle theory

Question 1

what does the kinetic particle theory state?

Answer 1

all matter is made of tiny particles and they move in constant random motion.

Question 2

why does solid have a fixed shape and a fixed volume?

Answer 2

1. • it is very closely packed in an orderly manner
   • held together by very strong forces of attraction
   • only have enough energy to vibrate and rotate about in their fixed positions; cannot move freely
2. • cannot be compressed- particles alrdy very close to one another; fixed volume

Question 3

why does liquid not have a fixed shape but has a fixed volume?

Answer 3

1. • particles arranged in a disorderly manner
     - have weaker forces of attraction than solid (strong)
     - particles have more kinetic energy than solid; not in fixed positions
     - move freely
2. particles are further away than solid but still paced quite closely together - cannot be compressed; has a fixed volume.

Question 4

why does gas not have a fixed shape and volume?

Answer 4

1. • particles are far apart from one another
     - weaker forces of attraction than solid
     - a lot of kinetic energy; not held together
     - move rapidly in any direction
2. particles have a lot more spaces between them- can be compressed when pressure is applied; does not have a fixed volume

Question 5

describe the particles of solids when it is heated until it melts?

Answer 5

• heat energy absorbed by particles and is converted into kinetic energy
• particles move about in their fixed positions
• when the temperature is high enough the vibration of the particles overcomes the forces of attraction between them
• break away from their fixed positions
• particles are now in a liquid state
• particles moves freely!

Question 6

what are the state changes of these processes?

1. melting
2. freezing
3. boiling
4. evaporation
5. condensation
6. sublimation
7. deposition

Answer 6

1. solid to liquid
2. liquid to solid
3. liquid to gas
4. liquid to gas
5. gas to liquid
6. solid to gas
7. gas to solid

Question 7

what is the difference between evaporation and boiling?

Answer 7

B: only occurs at boiling point
E: occurs before boiling point

B: occurs throughout liquid
E: occurs only at the surface of liquid

B: occurs rapidly
E: occurs slowly

Question 8

what are volatile liquids?

Answer 8

liquids that evaporate quickly at room temp

Question 9

why do solids sublime and what are some examples of solids which sublime?

Answer 9

• particles at the surface of the solid gains enough energy to break of the solid as gas particles
• examples: ammonium chloride, iodine and carbon dioxide

Question 10

a glass jar of air is inverted onto a glass jar of bromine with a cover to separate the gas jars. what is formed when the cover is removed and why?

Answer 10

• a homogeneous mixture of air and bromine is formed
• both gases are made of tiny particles moving at random
  > bromine particles into the spaces between the air particles and the air particles diffuse into the spaces between bromine particles

Question 11

gases with ______ relative masses diffuse faster than those with _____ relative masses.

Answer 11

1. lower

2. higher

Question 12

define diffusion.

Answer 12

diffusion is the net movement of particles from a region of higher concentration to a region of lower concentration

Question 13

the higher the ____ the higher the rate of diffusion.

Answer 13

temperature

Question 14

what is a matter?

Answer 14

a substance that has mass and occupies space. all living and non- living things are matter