Good Science Victorian Curriculum Year 7

INVESTIGATIONS
Investigation 5.4
Purifying muddy water
KEY SKILL
EXPLAINING RESULTS USING
SCIENTIFIC KNOWLEDGE
When you write a formal investigation report there is
always a discussion section that includes your analysis
and explanation of the data you collected. This is where
you get to explain your results by linking them to what
you already knew about the science of what you are
studying.
Hint #1: You can use the following sentence stem to write
about your results: ‘My data shows … and this makes sense
because …’.
AIM
To purify muddy water using decanting and filtration
MATERIALS
• soil and sand
• conical flask
• 250 mL beaker
• filter funnel
• filter paper
• glass stirring rod
• teaspoon
• wash bottle
METHOD
1 Copy the results flowchart into your notebook.
2 Half fill the beaker with water.
3 Add 1 teaspoon of soil into the beaker and stir until
a suspension forms.
4 Add 1 teaspoon of sand into the beaker and allow
the sand to settle to the bottom.
5 Fold the filter paper as shown and place it in
the funnel.
6 Set up the filtration apparatus as shown.
7 Carefully pour the mixture from the beaker into the
conical flask by decanting, without disturbing the
sand on the bottom of the beaker.
8 Record your observations in the flowchart.
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156 GOOD SCIENCE VICTORIAN CURRICULUM 7