A ‘hypothesis’ is based on scientific theories or life experience. It is a temporary explanation to a question. It may not be correct, so it needs to be verified by scientific methods. Proposing and verifying a hypothesis need imagination and creativity.
It seems that the water surface is like a layer of elastic rubber covering the water. That’s why the water does not overflow.
2. Propose a hypothesis
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Does the volume of ice decrease when it melts?
Let’s verify Fred’s hypothesis.
Hypothesis: Ice contracts when it melts, preventing water from overflowing. That is to say, water expands when it freezes.
Hypothesis
3. Test the hypothesis
Activity Booklet 16
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Test
(1) Prepare a glass of water (about 70% full). Mark the water level with a red rubber band.
(2) Put the glass into a freezer until the water freezes.
(4) Leave the glass at room temperature. Observe the
(3) Take the glass out of the freezer. Mark the level of
change in the water level after the ice melts.
the ice surface with a green rubber band.
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