Resource 3: Mr Sharma’s plan for an investigation

Table R3.1 Mr Sharma’s plan for an investigation.
Purpose of investigationTo develop investigation skills and support students understanding of change
Learning objectives

By the end of the investigation the students will be able to:

  • identify different changes that occur when substances are mixed
  • use observations to predict reversible and irreversible changes.
Resources neededPieces of paper, water, salt, flour, plaster of Paris, sand, vinegar, bicarbonate of soda, milk, containers for mixing
SafetyMake sure substances don’t go in students’ eyes.
Plan of demonstration

Students make objects by folding paper. How has the paper changed?

Tell students paper needed back – can they reverse the change?

Show burning paper. Write students’ observation on the chalkboard. Can it be reversed?

Write ‘reversible’ and ‘irreversible’ on chalkboard.

Setting up investigation

Tell students they are going to investigate changes when substances are mixed and decide whether they are reversible or irreversible.

Investigation questions: ‘What happens when substances are mixed?’ ‘Which changes are reversible?’

Ask students to work in groups. They have one small container and collect substances and mix and observe. Waste in bucket.

Draw results table on board. Students copy in to books to complete as they investigate.

SubstancesObservationsReversible or not?
Water and salt
Water and plaster
Water and flour
Water and sand
Milk and vinegar
Vinegar and bicarbonate of soda
Sand and flour
During investigationGo round and help students make observations by using questions. Make sure they are not using too much of each substance.
After investigationWhole class – ask what they observed – complete table on board. Which mixtures do they think are reversible? Why? How would they reverse them?

Resource 2: Talk for learning

Resource 4: Planning lessons