Kinetic Particle Theory

Question 1

define kinetic particle theory

Answer 1

• all matter is made up of tiny particles that are in constant, random motion
• moving particles have kinetic energy

Question 2

describe arrangement of solid liquid gas

Answer 2

solid: Closely packed; orderly arrangement

liquid: Quite closely packed; disorderly arrangement

gas: Very far apart; disorderly arrangement

Question 3

describe movement of solid liquid gas

Answer 3

Vibrate about fixed positions
Slide over one another
Move randomly at high speeds

Question 4

forces of attraction between particles solid liquid gas

Answer 4

very strong
strong
very weak

Question 5

kinetic energy of particles solid liquid gas

Answer 5

very low
low
high

Question 6

shape solid liquid gas

explain w movement

Answer 6

fixed
not fixed
not fixed

Question 7

volume solid liquid gas

explain w arrangement

Answer 7

fixed
fixed
not fixed

Question 8

compressibility solid liquid gas

explain w arrangement

Answer 8

cannot
cannot
can

Question 9

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

Answer 9

• Particles of a solid are held together by very strong forces of attraction and have very low kinetic energy.
• Particles only vibrate about their fixed positions and hence, solids have fixed shape.
• Particles are closely packed in an orderly arrangement and hence, solids cannot be compressed and have fixed volumes.

Question 10

why does a gas have a unfixed shape and a unfixed volume?

Answer 10

• Particles of a gas are held together by very weak forces of attraction and have high kinetic energy.
• Particles are very far apart and hence, gases have unfixed shape.
• Particles move randomly at high speeds in an disorderly arrangement and hence, gases can be compressed and have unfixed volumes.

Question 11

why does a liquid have a unfixed shape and a fixed volume?

Answer 11

• Particles of a liquid are held together by strong forces of attraction and have low kinetic energy.
• Particles can slide over one another and hence, liquids have unfixed shape.
• Particles are quite closely packed in an disorderly arrangement and hence, liquids cannot be compressed and have fixed volumes.

Question 12

describe changes in movement from one state to another

Answer 12

1. particles change from being closely packed in orderly arrangement to very far apart in disorderly arrangement
2. particles change from vibrating about fixed positions to moving randomly at high speeds

Question 13

define sublimation

Answer 13

process where solid changes directly into gas w/o going thru liquid state, occurs when particles at surface of solid have enough energy to break away & become gas

Question 14

examples of substances that sublime - 3

Answer 14

1. iodine
2. ammonium chloride
3. dry ice (co2)

Question 15

define diffusion

Answer 15

net movement of particles from a region of higher conc to a region of lower conc

Question 16

factors affecting rate

Answer 16

1. temp
2. ar/mr

Question 17

how does temp affect diffusion

Answer 17

as temp increases, particles hv more energy, move faster

Question 18

how does ar/mr affect diffusion

Answer 18

as ar/mr increases, rate of diffusion decreases

Question 19

why does temp increase between melting and boiling

Answer 19

as substances are heated, particles GAIN heat energy, CONVERTED TO chemical energy; since avg kinetic energy up, temp increase

Question 20

why does temp remain same during melting and boiling

Answer 20

during melting/boiling, heat absorbed by particles to overcome FORCES OF ATTRACTION between particles; since no change in avg kinetic energy, temp constant

Question 21

explain why gas spreads thru jar evenly

Answer 21

1. gases spread uniformly thruout container to form a HOMOGENOUS mixture of both gases
2. gas particles move randomly via diffusion to spread thruout container

Question 22

explain cotton wool in tube thing why ring not middle

Answer 22

1. molecules of gases diffuse into tube, meeting to produce ring
2. gases do NOT meet in middle bc mr diff, mr smaller = diffuse faster

Question 23

explain porous pot thingy e.g. inside pot is co, outside is h2

Answer 23

since mr h2 less than co, h2 diffuse into pot faster than co2 diffuse out, pressure in pot up, water level goes down

Question 24

what happens to water level if porous pot experiment carried out over long time e.g. inside pot is co, outside is h2

Answer 24

water level down first, then up bc h2 diffuse finish co2 hasnt, pressure down
after more time, water level become og bc diffusion of both r done, pressure same

Question 25

define atom

Answer 25

smallest particle of element that has its chemical properties

Question 26

define molecule

Answer 26

two or more atoms covalently bonded

Question 27

define element

Answer 27

pure substance that cannot be split into 2/more simpler substances by physical/chemical processes

Question 28

define compound

Answer 28

substance which contains two/more elements chemically combined in fixed composition

Question 29

define mixture

Answer 29

two/more substances physically mixed tgt in any proportion

Question 30

diffs between compounds & mixtures

Answer 30

1. Two or more elements chemically combined in a fixed composition.
   Two or more substances physically mixed together in any proportion.
2. Can only be broken down into its elements or into simpler compounds by chemical processes.
   Components of a mixture can be separated by physical means.
3. Physical and chemical properties of a compound are different from its constituent elements.
   The chemical properties of a mixture are the same as those of its components.