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Assessment for Learning Chemistry: what happens when substances dissolve? What happens when a precipitate forms?

Description

Assessment for Learning is an effective way of actively involving students in their learning. Each session plan comes with suggestions about how to organise activities and worksheets that may be used with students.

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A series of resources linked through concept or context which can be used in whole or in part during teaching or learning.

ADDITIONAL INFORMATION

If you teach primary science, click the headings below to find out how to use this resource:

Skill development

Children will develop their working scientifically skills by:

  • Asking their own questions about scientific phenomena.
  • Using a range of scientific equipment to take accurate and precise measurements or readings.
  • Using appropriate scientific language and ideas to explain, evaluate and communicate their findings.

Learning outcomes

Children will:

  • Observe that some materials will dissolve in liquid to form a solution, and describe how to recover a substance from a solution.
  • Demonstrate that dissolving, mixing and changes of state are reversible changes.

Concepts supported

Children will learn:

  • That some materials dissolve to form a solution.
  • That materials are still present when they have dissolved and that they haven’t disappeared.
  • That mass is conserved when dissolving and precipitating.

Suggested activity use

This activity can be used as a whole class investigation into the dissolving and precipitation processes, with children working in small groups to observe and answer the questions given. Alternatively, the activities could be demonstrated by an adult to stimulate discussion and questioning.

Practical considerations

It is important that the key vocabulary ‘dissolve’ and ‘precipitate’ are understood correctly by children in the introduction of this activity.

The ‘Dissolve’ task is more relevant to the primary science curriculum and could be more heavily focused on.

Conical flasks, stoppers and tubes may not be required for this activity if alternatives can be sourced, such as mini pop bottles and clean fromage frais pots.