GCSE Physics Density & particles questions by topic

Complete the table comparing the three states of matter.

1. (a)Complete the solid row’s arrangement.[1]
2. (b)Can a solid be compressed easily?[1]
3. (c)Can a liquid be compressed easily?[1]
4. (d)Complete the gas row’s arrangement.[1]

A student measures an object’s mass as 240 g and finds it displaces 80 cm³ of water.

1. (a)Calculate the object’s density in g/cm³.[2]
2. (b)State the name of the apparatus that measures displaced water.[1]
3. (c)State whether the object floats on water (density 1.0 g/cm³).[1]

Label each change of state.

1. (a)Solid to liquid.[1]
2. (b)Gas to liquid.[1]
3. (c)Liquid to solid.[1]
4. (d)Solid to gas directly.[1]

A cooling curve for a substance shows the temperature falling, then holding steady for a while, then falling again.

1. (a)State what happens during the steady (flat) section.[1]
2. (b)Explain why the temperature does not fall during it.[2]
3. (c)State whether the substance’s particles are gaining or losing potential energy in the flat section.[1]
4. (d)Name the change of state if the flat section is above room temperature and the substance ends as a liquid.[1]

This question is about the density required practical for a liquid.

1. (a)Describe how to measure the mass and volume of a sample of the liquid.[3]
2. (b)The empty measuring cylinder has mass 120 g; with 50 cm³ of the liquid it has mass 170 g. Calculate the density.[2]
3. (c)State one precaution that improves accuracy when reading the volume.[1]

A 2.0 kW kettle holds 0.80 kg of water at 20 °C. (c of water = 4 200 J/kg °C; L(vap) of water = 2 260 000 J/kg)

1. (a)Calculate the energy to raise the water to 100 °C.[2]
2. (b)Calculate the energy to boil away all the water at 100 °C.[2]
3. (c)Compare the two answers and explain the difference.[3]

Explain, using the particle model, each observation about gases.

1. (a)A sealed tin of gas warms up and the pressure gauge reading rises.[3]
2. (b)A balloon shrinks when taken into a cold room.[3]

An engineer needs 4 050 kg of aluminium (density 2 700 kg/m³) for a casting.

1. (a)Calculate the volume of aluminium needed.[2]
2. (b)The engineer melts 1.5 m³ of scrap aluminium instead. Show that this is just enough.[2]
3. (c)State one reason the real requirement might be slightly larger.[1]

A fixed mass of gas is trapped in a syringe at 120 kPa with the plunger at the 12 cm³ mark. (Higher)

1. (a)The plunger is pushed to 8.0 cm³ at constant temperature. Calculate the new pressure.[3]
2. (b)Explain the pressure increase using the particle model.[3]
3. (c)State the extra observation if the compression is done very quickly.[1]

A student measures the density of a glass marble: mass 16.5 g; before adding the marble a eureka can delivers 20 cm³ of water, after dropping the marble in it delivers 26.5 cm³.

1. (a)Calculate the marble’s volume.[1]
2. (b)Calculate the marble’s density.[2]
3. (c)The accepted density of this glass is 2.5 g/cm³. Calculate the percentage difference.[2]
4. (d)Suggest one measurement that could have caused the difference.[2]

A student claims: “Steam at 100 °C burns you more badly than water at 100 °C because steam is hotter.”

1. (a)Identify the error in the claim.[1]
2. (b)Write the correct explanation using latent heat.[3]
3. (c)Support it with a calculation for 5.0 g of steam condensing on skin (L = 2 260 000 J/kg).[2]

This question is about the density required practical for an irregular object and its evaluation.

1. (a)Describe the method with a eureka can and balance.[3]
2. (b)State the independent and dependent variables — or explain why they are not meaningful here.[2]
3. (c)The object displaces 32 cm³ and has mass 89.6 g. Calculate the density in kg/m³.[2]
4. (d)State one source of error and an improvement.[1]