physics chapter 8

Question 1

what are the three types of states

Answer 1

solid, liquid and gas

Question 2

what are the properties of a solid

Answer 2

fixed shape and volume, high density, incompressible, cannot flow

Question 2

describe the solid

Answer 2

Solids have a definite shape and a definite volume

Solids cannot flow and are not compressible

Question 3

what are the properties of a liquid

Answer 3

fixed volume but no fixed shape, high density, incompressible, can flow and take the shape of the container

Question 3

describe the liquid

Answer 3

liquids have no definite shape but do have a definite volume

Liquids are able to flow to take the shape of a container but they are not compressible

Question 4

describe the gas

Answer 4

Gases have no definite shape and no fixed volume

Gases can flow to take the shape of their container and are highly compressible

Question 5

how does matter change from one state to another

Answer 5

the state of matter depends on the temperature and the pressure the matter is under. changing the temperature of matter can change it from one state into another

Question 6

how does solid become gas

Answer 6

when a solid is heated, it melts into a liquid at its melting point. a liquid that is heated will boil and become gas at its boiling point.

Question 6

how does gas become solid

Answer 6

when a gas is cooled to its boiling point, it will condense into a liquid. a liquid will freeze into a solid when cooled to its melting point.

Question 6

what is the kinetic particle model of the different states

Answer 6

the kinetic model of matter states that tiny particles that make up matter are always in continuous random motion. this model is used to help us understand the properties of each state of matter

Question 6

what is the arrangement of particles like in a liquid

Answer 6

The molecules are still close together (no gaps) but are no longer arranged in a regular pattern

The molecules are able to slide past each other

Question 6

what is the arrangement of particles like in a solid

Answer 6

-The molecules are very close together and arranged in a regular pattern

The molecules vibrate about fixed positions

Question 7

what is the arrangement of the particles like in gas

Answer 7

The molecules are widely separated - about 10 times further apart in each direction

The molecules move about randomly at high speeds

Question 8

describe the distance between the particles of a solid

Answer 8

the distance between the particles is small, so solids have a high density and are incompressible

Question 9

how is the force like in the particles of a solid

Answer 9

as they are close together, the particles solids have strong attractive forces between them. that is why solids have a fixed volume and a fixed shape.

the strong attractive forces hold the particles in fixed positions. that is why solid cannot flow

Question 10

describe the distance between the particles of a liquid

Answer 10

the distance between the particles in liquids is slightly greater than in solids. that is why liquids are slightly less dense but are still incompressible and have a fixed volume

Question 11

how is the force like in the particles of a liquid

Answer 11

as the particles are slightly further apart, the attractive forces are not as strong as the particles in solids. the particles in liquids can move around freely. that is why liquids can flow. they do not have a fixed shape but take the shape of their container

Question 12

describe the distance between the particles of gas

Answer 12

the distance between the particles in gases is much greater. that is why gases have low density and are compressible

Question 13

how is the force like in the particles of gas

Answer 13

as the particles are far apart, there is very little attractive force between them. that is why gases have no fixed volume or shape.

the particles move around at high speed, so gases can flow and fill the space they are put into.

Question 14

what happens to the particles when temperature increases

Answer 14

when an object is heated, the temperature of the object increases. the average kinetic energy of the particles in the object increases and the particles in the object increases and the particles move or vibrate faster

Question 15

at which temperature do the particles have the lowest kinetic energy

Answer 15

-273 degrees celsius, this temperature is also known as the absolute zero

Question 16

what is an example of microscopic particles

Answer 16

pollen grains and smoke particles

Question 17

what is the brownian motion

Answer 17

the brownian motion refers to the random movement of microscopic particles in a fluid due to the collisions by the molecules of the fluid. we can only see microscopic particles under the microscope as the molecules are too small to be seen

Question 18

how does brownian motion occur

Answer 18

• These light, fast-moving atoms and molecules collide with the larger microscopic particles
• The presence of the light, fast moving atoms and molecules is inferred from the motion of the microscopic particles

Question 19

how does pressure of a gas vary withs its pressure

Answer 19

when the temperature of the air in the tyres increase, the pressure of the air in the tyres also increase. for a fixed volume and mass of gas, increasing its temperature results in an increase in the speeds of the gas particles

Question 19

how does the pressure of gas vary with its volume

Answer 19

using the kinetic particle model of matter, a decrease in the volume of gas means that the number of particle per unit volume increases. therefore, the gas particles collide more frequently with the inner surface of the syringe and this result in a greater pressure as shown on the pressure gauge.

Question 20

when changing the state, what changes

Answer 20

The only thing that changes is its energy Changes of state are physical changes and so they are reversible

Question 21

how is the density like in a solid

Answer 21

high

Question 22

how is the density like in a liquid

Answer 22

medium

Question 23

how is the density like in a gas

Answer 23

low

Question 24

what is the energy of the particles like in a solid

Answer 24

low energy

Question 25

what is the energy of the particles like in a liquid

Answer 25

greater energy

Question 26

what is the energy of particles like in a gas

Answer 26

highest energy

Question 27

how can we study the brownian motion of the smoke particles

Answer 27

1. set up the apparatus including the microscope, torchlight, glass cell containing smoke 2. seal a glass cell containing some smoke and place it under the microscope 3. focus the microscope such that the smoke particles in the glass cell appear as bright dots. the smoke particles appear as bright dots because they scatter the light that shines on them. 4. observe the motion of the smoke particles

Question 28

identify the observations made while studying the brownian motion of smoke particles

Answer 28

1. the smoke particles moved in a random manner 2. the larger the particles, the less vigorous the motion

Question 29

how do gas exert pressure

Answer 29

the gas particles move in a random manner in all directions. they collide with one another with the walls of the container. the pressure on the container is caused by the constant collisions of many particles with its walls

Question 30

If the temperature T of an ideal gas is constant, then Boyle’s Law is given by:

Answer 30

This means the pressure is inversely proportional to the volume of a gas it can be written as pV= constant

Question 31

The relationship between the pressure and volume for a fixed mass of gas at constant temperature can also be written as:

Answer 31

p1v1=p2v2