Simple kinetic molecular model of matter

Question 1

the physical properties of solid liquid gas

Answer 1

solid: fixed shape and volume; incompressible
liquid: no fixed shape but fixed volume; incompressible
gases: no fixed shape nor fixed olume; compressible

Question 2

particle arrangements of solid liquid gas

Answer 2

solid: usually in fixed pattern
liquid: no fixed pattern
gas: no fixed pattern

Question 3

inter particle distance of solid liquid gas

Answer 3

solid: close 10^-10m
liquid: close 10^-10m
gas: far apart 10^-7 or ^-6)

Question 4

inter particle forces of solid liquid gas

Answer 4

solid: very strong
liquid: weak
gas: negligible

Question 5

particle speeds of solid liquid gas

Answer 5

solid: vibrating about fixed position
liquid: sliding over each other
gas: moving about at high speeds

Question 6

what is temperature

Answer 6

temperature is the speed of a particle

Question 7

what determines the state of matter(solid liquid gas)

Answer 7

inter-particle forces

Question 8

what does inter-particle forces do

Answer 8

they are what keeps molecules ibn their fixed positions.

Question 9

how does matter change form

Answer 9

once the molecules gain sufficient energy, they overcome the inter-particle forces and start to slide over / break free from each other and start to move at high speeds

Question 10

equation relationship between pressure temperature and volume

Answer 10

pv = nRT
P = pressure
V = volume
n = amount of substance
R = ideal gas constant(0.0821)
T = temperature

Question 11

amonton’s law

Answer 11

a change in pressure of a fixed mass of gas at constant volume is caused by a change in temperature of the gas
T∝P

Question 12

charles law

Answer 12

a change in volume of a fixed mass of gas at a constant pressure is caused by a change in temperature of the gas
temp change->volume change
V∝T

Question 13

boyle’s law

Answer 13

a change in pressure of a fixed mass of gas at constant temperature is caused by a change in volume of the gas
P∝1/V

Question 14

for all the laws to work what is one criteria that all scenarios need

Answer 14

fixed mass of gas

Question 15

amonton’s law equation

Answer 15

P1/T1 = P2/T2
they should usually have 3 of 4 in the qn

Question 16

boyle’s law equation

Answer 16

P1V1 = P2V2
they should usually have 3 of 4 in the qn

Question 17

charle’s law equation

Answer 17

V1/T1 = V2/T2
they should usually have 3 of 4 in the qn

Question 18

how to know when to use amonton’s law

Answer 18

when theres a fixed volume, and fixed mass of gas
fixed mass of gas is a must for all 3 laws
fixed V, cuz this law test for P n T

Question 19

how to know when to use boyle’s law

Answer 19

when theres fixed temperature, and fixed mass of gas
fixed mass of gas is a must for all 3 laws
fixed T, cuz this law test for P n V

Question 20

how to know when to use charle’s law

Answer 20

when theres fixed pressure, and fixed mass of gas
fixed mass of gas is a must for all 3 laws
fixed P, cuz this law test for V n T

Question 21

what is thermal equilibrium

Answer 21

2 points r consider to be in thermal equilibrium if there is no net flow of thermal energy when they are connected by a path permeable to heat
NOT AFFECTED BY VOLUME
50kg of water to 50deg <=> 0.50kg of water to 50deg

Question 22

what is thermal energy

Answer 22

its basically the same as temperature which is basically the same as kinetic energy of the particles
Temperature increase → Thermal energy increase → Particles’ kinetic energy increases → Particles move faster.

Question 23

temperature real meaning

Answer 23

average kinetic energy of particles in an object

Question 24

what are emitters and absorbers

Answer 24

all objects constantly absorb and emit radiation. hence, we must consider the net flow of energy,
net emitter of radiation: emits radiation at a faster rate compared to absorption
net emitter of radiation: absorbs at a faster rate compared to emission

Question 24

radiation meaning

Answer 24

the transfer of thermal energy in the form of electromagnetic waves, such as infrared radiation, without the aid of a medium.

Question 25

conduction meaning

Answer 25

conduction is the transfer of thermal energy through a medium without any flow of the medium particles at a region of higher temperature **vibrate vigorously** about their **fixed positions**. they then **collide** with with neighbouring particles to **transfer kinetic energy** to particles at regions of lower tempertaure, until thermal equilibrium is reached. As a result, **energy is transferred with no transfer of particles**

Question 26

why are liquids and gases poor conductors of heat compared to solids?

Answer 26

the particles in liquids and gases are spaced further apart than those in solids. the **frequency of collisions** is thus **lower** in liquids and gases. hence, the rate of energy transfer by collisions between particles is lower. as a result, the rate of conduction is lower in liquids and gases, making them poor conductors of heat compared to solids

Question 27

why are solids metals better conductorss of heat than solid non-metals?

Answer 27

metals are better conductors of heat than non-metals due to the presence of **free electrons** that are able to *move around the medium freely**, which increases the rate of thermal energy transfer by conduction.

Question 28

convection meaning

Answer 28

convection is the transfer of thermal energy by means of convection currents in fluids due to a difference in density. in most fluids, an increase in temperature corresponds to an increase in volume. Hence, when a region of a fluid is heated, it expands and thus density decreases. this region will then rise in the fluid as it is of a lower density compared to its surroundings. regions of higher density sink to occupy the space left behind. this creates a convection current

Question 29

why does hot gas/liquid rise

Answer 29

molecules in the gas/liquid move faster and spread out, increasing the volume of the air. Since density is mass per unit volume, when the air expands, its density decreases. lower density = rise

Question 30

surface physical properties that affect thermal heat transfer

Answer 30

-temperature, higher temperatures increase radiant heat transfer -area, larger areas increase radiant heat transfer -colour, dark surfaces absorb more solar radiation and reflects less -texture, shinier surface reduces radiant heat transfer

Question 31

internal energy meaning

Answer 31

u(IE) = KE + PE KE = when the object changes temp PE = when the object changes state (gas,liquid,solid) when either one of them increases or decreases so does internal energy eg. gas condensing, PE decreases -> IE decreases

Question 32

heat capacity definition

Answer 32

Q = C Δθ Q = the energy required to change the temperature C = heat capacity Δθ = temperature change

Question 33

specific heat capacity definition

Answer 33

Q = m c Δθ Q = the energy required to change the temperature c = heat capacity m = mass of the material Δθ = temperature change

Question 34

calculate the amount of heat required for a phase change (like melting, freezing, boiling, or condensation) without a change in temperature.

Answer 34

QL = m l