Pickles AcademyStart for free

States of matter – practice for Years 6–8

Sample questions on States of matter with the right answer and a worked solution, from easy to hard. In the Pickles Academy app a child gets new questions of the same kind every time, so they can't just learn the answers by heart.

Subject
Physics
Year
Years 6–8
Curriculum area
Matter and objects

Question types: States of matter and changes of state

Rule: States of matter

A solid keeps its shape and volume. A liquid keeps its volume but takes the shape of its container. A gas fills all the space.

Melting: solid → liquid, freezing the other way. Evaporating, boiling: liquid → gas, condensing back. Sublimation: solid → gas.

Example: Ice melts at 0 °C and water boils at 100 °C (at normal pressure).

Watch out: Water is an exception: it expands when it freezes. That is why ice floats and a full bottle in the freezer cracks.

Sample questions

  1. Question 1 Easy

    Fill in the right words.

    1. A liquid turning into a solid is called …. (freezing / evaporation / melting / sublimation)
    2. At normal pressure, pure water boils at …. (120 °C / 50 °C / 100 °C / 0 °C)
    3. A gas turning into a liquid is called …. (condensation / sublimation / melting / evaporation)
    Show the solution
    Answer:
    1. A liquid turning into a solid is called freezing.
    2. At normal pressure, pure water boils at 100 °C.
    3. A gas turning into a liquid is called condensation.

    How it works: A liquid turning into a solid is called freezing. At normal pressure, pure water boils at 100 °C. A gas turning into a liquid is called condensation.

  2. Question 2 Normal

    Fill in the right words.

    1. At normal pressure, pure water freezes at …. (0 °C / 4 °C / −10 °C / 100 °C)
    2. Evaporation happens at any temperature, from the … of a liquid. (whole volume / bottom / surface)
    3. A solid turning straight into a gas is called …. (sublimation / evaporation / melting / deposition)
    4. A liquid has a fixed volume, but its … changes with the container. (mass / volume / shape)
    Show the solution
    Answer:
    1. At normal pressure, pure water freezes at 0 °C.
    2. Evaporation happens at any temperature, from the surface of a liquid.
    3. A solid turning straight into a gas is called sublimation.
    4. A liquid has a fixed volume, but its shape changes with the container.

    How it works: At normal pressure, pure water freezes at 0 °C. Evaporation happens at any temperature, from the surface of a liquid. A solid turning straight into a gas is called sublimation. A liquid has a fixed volume, but its shape changes with the container.

  3. Question 3 Hard

    Fill in the right words.

    1. A liquid turning into a solid is called …. (freezing / evaporation / melting / sublimation)
    2. At normal pressure, pure water boils at …. (120 °C / 50 °C / 100 °C / 0 °C)
    3. A gas turning into a liquid is called …. (condensation / sublimation / melting / evaporation)
    4. A solid turning into a liquid is called …. (condensation / boiling / melting / freezing)
    Show the solution
    Answer:
    1. A liquid turning into a solid is called freezing.
    2. At normal pressure, pure water boils at 100 °C.
    3. A gas turning into a liquid is called condensation.
    4. A solid turning into a liquid is called melting.

    How it works: A liquid turning into a solid is called freezing. At normal pressure, pure water boils at 100 °C. A gas turning into a liquid is called condensation. A solid turning into a liquid is called melting.

Related topics

All Physics topics

Keep practising in the app

In a minute, your child has their own avatar and a first task. Free, no ads, data in the EU.

Start for free