Changes resources

Task: Identify the variables for testing how fresh water and salt water affect rusting. Assessment focus: planning a fair test.

For this practical students observe some activities which illustrate melting and dissolving. They write sentences about what they observe and then write what they think melting and dissolving mean.

Students indicate for each of six different variables those that need to be kept the same for an investigation about dissolving different types of sugar.

Students are provided with a graph of the heating curve for octane. Students use this to answer questions about state, temperatures, and changes of state.

Students use a table of information on melting points and boiling points of six different substances to answer questions about states of matter.

The liquid range for four common substances has been provided. Students use this to answer questions about melting point, boiling point, and state.

Students look at two diagrams. The first shows iron nails in test tubes with boiled water or tap water, the second shows iron nails with moisture either present or absent. Students answer five questions about these investigations.

Students evaluate a fair test about whether salt or sugar solution dissolves faster.

Select the correct pair to set up a fair test. Assessment focus: controlling variables.

Students are given an outline of an investigation on metal corrosion and a graph of some results. Students' ability to interpret the graph and knowledge of fair testing is assessed via short answer questions.

Students identify which substances undergo a permanent change when they are mixed together.

Students decide on the variables that will make an experiment about boiling water a fair test. Assessment focus: Recognising multiple variables.

Students are given a graph that shows how many days it took for bread placed in different areas to grow mould. Students use this graph to answer three short questions.

Task: Select which state of water applies to a list of places where water can be found. Assessment focus: states of water.

Students identify the changes of state that are occurring in a diagram showing the separation of fresh water from seawater.