Paper 1 - Solids, Liquids and Gases

Question 1

What is the equation for density?

Answer 1

ρ = m/V

Question 2

Describe a practical to investigate density using direct measurements of mass and volume.

Answer 2

• Displacement method
• Record mass of object using top-pan balance
• Fill a displacement can with water until just below the spout
• Place a gradulated beaker below the exit of the spout
• Slowly lower object into displacement can to avoid splashing
• Record volume of water displaced that flows into the gradulated beaker as this is the volume of the object
• Using ρ = m/V, substitute in the values to obtain a value for density
• Repeat 3 times and take an average

Question 3

What is the equation for pressure?

Answer 3

p = F/A

Question 4

How does the pressure at a point in a gas or liquid act?

Answer 4

The pressure at a point in a gas or liquid at rest acts equally in all directions

Question 5

What is the equation for pressure difference?

Answer 5

p = ρ × g × h

Question 6

How do gases exert pressure?

Answer 6

Molecules in a gas have random motion and that they exert a force, and hence a pressure, on the walls of a container

Question 7

What is the temperature absolute zero?

Answer 7

0K or -273℃

Question 8

How do you convert from ℃ to Kelvin?

Answer 8

Subtract 273 from the value for ℃

Question 9

Why does an increase in temperature result in an increase in the average
speed of gas molecules?

Answer 9

• Molecules gain kinetic energy
• Molecules move more rapidly and more randomly

Question 10

What is the relationship[ between the Kelvin temperature of a gas and the average kinetic energy of its molecules?

Answer 10

The Kelvin temperature of a gas is proportional to the average kinetic energy of its molecules

Question 11

In a fixed amount of gas, what is the relationship between pressure and volume at constant temperature?

Answer 11

• If the volume is decreased, the pressure will increase
• Inversely proportional
• Same number of particles in a smaller volume
• More frequent and more forceful particle collisions with the wall of the container
• Which increases the pressure

Question 12

In a fixed amount of gas, what is the relationship between pressure and Kelvin temperature at constant volume?

Answer 12

• If Kelvin temperature is increased, the pressure will increase
• Directly proportional
• The particles gain kinetic energy
• Particles move more rapidly and randomly
• More frequent and more forceful particle collisions with the wall of the container
• Which increases the pressure

Question 13

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

Answer 13

p1 / T1 = p2 / T2

Question 14

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

Answer 14

p1V1 = p2V2

Question 15

What must you always do in a gas laws/gay Lussac’s law question involving pressure and temperature?

Answer 15

Convert temperature from Celsius ℃ to Kelvin K