P3

Question 1

What is internal energy ?

Answer 1

The internal energy of a system is the total energy that its particles have in their kinetic and potential energy stores .

Question 2

What happens as a substance melts ?

Answer 2

When a substance melts,particles are moved apart against their electrostatic attraction .Their movement slows and prevents the temperature of the substance from rising until the change of state is complete.

Question 3

What happens when a substance freezes .

Answer 3

The attractive force accelerates particles as they move closer together and the particles increased movement prevents the temperature of the substance from falling until the change of state is complete

Question 4

What happens when a substance vaporises?

Answer 4

Particles are moved apart against their electrostatic attraction , that holds them together .Their movement slows and prevents the temperature of the substance from rising until the change of state is completes .

Question 5

What happens when a substance condenses ?

Answer 5

Particles are pulled together by their electrostatic attractions.The attractive force accelerates the particles as they move closer together and the particles increased movement prevents the temperature of the substance from falling until the change of state is complete

Question 6

What is latent heat?

Answer 6

The energy needed for substance to change state

Question 7

What happens when a change of state occurs ?

Answer 7

The energy supplied changes the internal energy but not the temperature.

Question 8

What is the specific latent heat of fusion ?

Answer 8

The energy transferred from 1kg of a substance changing from liquid to solid at a constant pressure.

Question 9

What is the equation for thermal energy transferred for a change of state ?

Answer 9

Q=ml

Question 10

What is the specific heat of vaporisation.

Answer 10

The energy transferred from 1kg of a substance changing from liquid to gas at constant pressure

Question 11

How many pascals is atmospheric pressure ?

Answer 11

1.01 x10 to the power of five

Question 12

What is the equation for pressure ?

Answer 12

Pressure=force divided by area

Question 13

What is the equation for momentum ?

Answer 13

Momentum=mass x velocity

Question 14

What did Boyles law state?

Answer 14

As the kinetic energy of the molecules increases,the temperature of the gas increases

Question 15

What is the equation that links pressure,constant and volume

Answer 15

Pressure x volume =constant
P1V1 =P2V2

Question 16

How do you convert from degrees Celsius to kelvin’s

Answer 16

Degrees c +273

Question 17

I what is the pressure law equation?

Answer 17

P after divided by T after =P before divided b T before

Question 18

In pressure law,what must temperature be in .

Answer 18

Kelvins

Question 19

What is density ?

Answer 19

The mass of each unit of volume of a material

Question 20

What is the equation for density ?

Answer 20

Density = mass / volume

Question 21

What is density measured in ?

Answer 21

Kg/m3 or g/cm 3

Question 22

What are the similarities and differences between the kinetic theory and particle model of matter ?

Answer 22

The particle model of matter is used to explain the behaviour of matter based on the idea that it is all made up of tiny particles .It also helps to explain various properties of matter such as density.On the other hand, the kinetic theory of matter is a specific theory within the particle model framework which explains the behaviour of matter in terms of the movement of particles.It says that particles are in constant motion and the temperature of a substance is related to the average kinetic energy if its particles .