SP14

Question 1

What is the movement and arrangement of particles in solids?

Answer 1

• Can vibrate about fixed positions
• Packed tightly together in a a regular arrangement

Question 2

What is the movement and arrangement of particles in liquids?

Answer 2

• Can move around each other and flow
• Arranged in a random way, with particles still touching each other

Question 3

What is the movement and arrangement of particles in gases?

Answer 3

• Particles are moving around quickly and randomly
• Particles are far apart and expand to fill their container

Question 4

CP: How to measure density of liquid?

Answer 4

• Place an empty beaker on a balance and set it to 0
• Use a measuring cylinder to measure out 50 cm^3 of water, before adding this to the beaker and weighing
• Density is equal to mass divided by volume

Question 5

CP: How to measure density of a solid?

Answer 5

• Use a balance to find mass of a solid
• Fill a displacement can with water until just the point where water begins to exit the spout
• Hold a measuring cylinder under the spout and add solid object into the can
• Read volume of water displaced in measuring cylinder, which is the volume of the solid
• use the formula of density equals mass divided by volume

Question 6

Why are solids the most dense state of matter?

Answer 6

• The particles are most tightly packed together, with the fewest intermolecular spaces between them

Question 7

What is specific heat capacity?

Answer 7

• This is the amount of energy it takes to increase the temperature of 1kg of a substance by 1 degree

Question 8

What is specific latent heat?

Answer 8

• This is the amount of energy it takes to make 1kg of a substance change state

Question 9

What is thermal insulation and some examples?

Answer 9

• This is the process of reducing heat energy transfers between objects
• It can be done by putting air gaps between layers, which trap heat energy trying to enter or escape

Question 10

CP: obtain a temperature-time graph of ice as it melts

Answer 10

• Put a boiling tube full of crushed ice into a heat-proof beaker
• Place a thermometer in the ice and note the temperature
• Place beaker on a tripod and gauze, before pouring boiling water from a kettle on it and keeping it warm with a Bunsen burner
• Record and note temperature every minute, until three minutes after all the ice has melted

Question 11

CP: Find the specific heat capacity of water

Answer 11

• Put a polystyrene cup in a beaker on a balance and set it to 0
• Fill the cup with water and write down the mass
• Put a thermometer and immersion heater in the water, before connecting it to a joulemeter
• Record temperature of water, before switching the heater on and waiting for five minutes
• After 5 minutes, record temperature of water and reading on the joulemeter
• Use equation for SHC to find it

Question 12

How is gas pressure formed?

Answer 12

• Gas particles move around randomly in their container
• As they collide with the wall of their container, it causes pressure

Question 13

How does increasing temperature increase the gas pressure?

Answer 13

• As the gas particles will have more kinetic energy, there will be more frequent collisions with the walls of their containers, increasing the pressure

Question 14

What is absolute zero?

Answer 14

• The coldest temperature in the solar system
• It’s -273 degrees Celsius
• At this temperature, the gas particles will have no kinetic energy, so there will be 0 gas pressure

Question 15

How do you convert from Celsius and Kelvin?

Answer 15

• Kelvin starts at absolute zero, with 0K being equivalent to -273 Celsius
• However, if you move up by 1K, its the same as moving up by 1C
• So to go from Celsius to Kelvin, you add 273

Question 16

How can gases be compressed or expanded?

Answer 16

• By squeezing gas particles into a certain volume, it increases pressure as there will be more frequent collisions between particles and the walls of the container

Question 17

In which direction does gas pressure produce a force?

Answer 17

• Gas produces a net force at right angles to the surface

Question 18

How can decreasing volume increase gas pressure?

Answer 18

• There will be the same number of particles in a smaller volume, leading to more frequent collisions between particles and the walls of containers, increasing pressure

Question 19

How does doing work increasing gas temperature?

Answer 19

• Work done (such as pumping a bike pump), energy is being transferred to the gas inside the pump
• This results in gas particles moving faster, which we detect as a temperature increase