# Thermal energy Flashcards

1
Q

Kinetic energy eqaution

A

E = 1 mv sqaured
2

2
Q

What does theoretical mean

A

Based on ideas

3
Q

What does empirical mean

A

Based on proof

4
Q

What did we see when we looked through the microscope at the smoke particles

A

When we looked through the microscope we saw tiny white smoke particles moving in random directions because they were bouncing off of the air particles the reason they move in this motion is because they have more impact on one side of the atom and the other causing a resultant force where the more impacted the smoke moves in that direction which changes randomly so there is a zigzag motion

5
Q

What is the boiling point and melting point of argon oxygen and water

A

Boiling. Melting
Argon. -185. -189
Oxygen -183. -218
Water. 100. 0

6
Q

Definition of temperature

A

It is the degree of hotness of an object and it can be measured by thermometer temperature can be expressed by Celsius Fahrenheit or kelvin scale

7
Q

Definition of heat

A

It is the energy which travels from high temperature to low temperature in a matter it is also called thermal or internal energy it is measured in joules

8
Q

What is Brownian motion

A

Random movement of particles of liquids or gases

9
Q

What is the proof of kinetic theory

A

Is Brownian motion less smoke particles move in random direction is hitting other particles as well as that when you heat atoms up the pressure builds causing the atoms to move quicker therefore more kinetic energy

10
Q

Proof of kinetic theory examples

A

Brownian motion
Particles moving around create pressure less particles high up less pressure expansion of gases in aeroplane
Pumping up a timer
Expansion of a liquid
Expansion of a solid

11
Q

What is absolute zero

A

0k or -273 degrees Celsius

12
Q

How does the expansion of metal happen when heated

A

It’s a metal is heated the particles inside it gain more kinetic energy which means they move quicker therefore the increase in speed hitting each other more times and therefore expanding the solid

13
Q

The expansion of liquids

A

When the liquid is heated the molecules have more energy and move more vigourously the movement of the molecules overcome the forces of attraction between the molecules allowing them to move freely loss the volume of the liquid increases

14
Q

The contraction of liquids

A

Lower temperature in the molecules have less energy and move closer to each other this causes the volume of the liquid to decrease

15
Q

Can solids expand and contract a lot

A

Only a small amount because particles are held tightly by inter molecular forces around a fixed position

16
Q

Can gases expand and contract a lot

A

Quite large contraction and expansion because atoms held by weaker forces

17
Q

Can gases expand and contract a lot

A

Yes large amounts expansion increases pressure in the container because particles move more quickly and hit container with more force contraction reduce pressure in a container because particles move slower and hit container with less force

18
Q

How does a solid expand

A

When heated The particles in a solid move around quicker therefore hitting the container and other particles with a bigger force which pushes the particles further apart therefore expanding

19
Q

Where does conduction occur

A

In solids or metals

20
Q

Where does convection occur

A

Liquids and gases

21
Q

A

From any hot object liquid or gas

22
Q

What is conduction

A

It is the heat transfer by means of faster pop molecules motion within the material without any shift of the material as a whole if one end of a metal rod is it higher temperature than energy will be transferred towards the colder end because the higher speed particles will collide with the slower ones with a net transfer of energy to the silver ones all metals are good conductors because of delocalised electrons

23
Q

What is convection

A

It is heat transferred by the motion of fluids such as air or water when they are heated fluid is cause to move away from the source of heat carrying energy with it convection above a hot surface occurs because hot air expands becomes less dense and rises hot water is less dense than cold water and rises causing convection currents which transfer energy

24
Q

A

It is the flow of heat from one place to another by means of electromagnetic waves the colour and shiny Ormat surface changes the amount of radiation omitted and absorbed

25
Q

What makes things sink or float

A

The density of the object
The weight of the object
If it has Air it

25
Q

What makes things sink or float

A

The density of the object
The weight of the object
If it has Air it

26
Q

What makes something float

A

Is the density of the object is less than the surrounding density

27
Q

What makes things sink

A

If the density of the object is greater than the surrounding density

28
Q

What are a few examples of convection

A

The mineshaft experiment – lighting a fire in a mine carbon dioxide goes up air goes down into the mine so miners can breathe
Lighting the paper – the density of the object is less than the surrounding density rises heat rises in air
The purple tube on one side as heated causing fluid to go up one side is colder causing fluid to sink therefore convection flow
Light bulb fan – when the fan is on top of the lightbulb heat rises therefore the particles push the fan round

29
Q

What are the two situations of radiation

A

30
Q

Why is the matte black a better absorber of heat than the shiny silver

A

Because matte black is dull and absorbs the heat the shiny silver reflects the heat off of it

31
Q

Difference between evaporation and boiling

A

Evaporation happens at any time
Only happens surface of object
Causes a drop in the temperature
No bubbles
Opposite of condensation
Boiling happens at boiling point happens to rub the liquid doesn’t cause drop in temperature the air bubbles and is the opposite of condensation

32
Q

How do you calculate the specific heat capacity

A

= E
M(final temp-starting temp)

33
Q

What does SHC stand for

A

Specific heat capacity

34
Q

How do you calculate the energy in

A

Current volatagetime

35
Q

When heating water from an ice cube why does the temperature not increase at the melting point and boiling point of it

A

At the melting point it stops increasing in temperature because the energy is being used to break the intermolecular bonds between the solid to turn into a liquid then heats up till the boiling point and the same thing happens the energy is used to break the intermolecular forces between the liquid to turn it into a gas