Half Term 5 Slg Test Answers

Question 1

Find the density of a rock

Answer 1

• Measure the mass of the rock by placing it on a balance
• immerse the rock in water
• use eureka can to displace water
• measure the volume of water displaced
• Find density using the equation density = Mass/Volume

Question 2

Explain in terms of particles why the pressure of air inside the glass jar decreases

Answer 2

1) walls further apart
2) fewer collisions between particles and walls per second
3) means force on walls is lower

Question 3

Before the rubber sheet is pulled down, the air inside the jar is at atmospheric pressure.

The volume of the gas inside the jar increases from 110cm to 140 cm

Calculate the pressure inside the jar after the rubber sheet is pulled down
(Atmospheric pressure = 101 kPa)

Answer 3

p1v1 = p2v2
101x110 = p2 x 140
p2 = 101x110/140
p2 = 79,000 Pascals

Question 4

Explain why balloons start to expand when the rubber sheet is pulled down.

Answer 4

1) pressure outside balloon is lower than inside the balloon
2) pressure difference causes a force
3) force is outwards on balloon
4) forces cause extension of balloon

Question 5

Define specific heat capacity

Answer 5

Energy to change temperature by 1 degree per kilogram of mass

Question 6

Give two ways they could improve their method to increase the accuracy of their value of specific heat capacity

Answer 6

• place a lid on top
• leave block in oven for longer

Question 7

What is 0 degrees in kelvin

Answer 7

273 kelvin

Question 8

What is the relationship between pressure and kelvin temperature of a fixed mass of gas at a constant volume

Answer 8

P1/T1 = P2/T2