KINDLE COVE
PSLE Experimental Questions Made Simple
Experimental questions can seem challenging at first, but many of them actually follow common answering patterns. By learning the correct structure and style of answering, students can gain confidence and avoid losing unnecessary marks.
In these notes, we have compiled four common types of PSLE experimental questions together with effective answering techniques to help students write clearer, more complete scientific explanations during exams.
1. Question: What is the aim of the experiment?
Answer should start with “To find out / To investigate…” how “the cause / manipulated variable” affects the “result / the dependent variable”.
For example:
Answer: To find out if the number of leaves (cause) affect the amount of oxygen produced (effect)
2. Question: What is a control set-up?
Remember the 'COC' (Compare, Observe, Confirm) :
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Use the writing structure as follows:
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compare with and observe the manipulated set-up, so as to confirm that ...."state the aim"
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For example:
Answer: A control set-up, Set-up A, is used to compare and observe with the changed variable, set-up B, to confirm that the presence of Chemical X affects the growth of the fish (write out the aim).
3. Question: Why do we repeat the experiment a few times?
Answer: To ensure that the results are consistent and reliable.
4. Question: Why do we need to ensure that the experiment is a fair one?
OR Why do we have to keep all other variables (eg. amount of water) constant?
Tip: We have to show that the other variables will also affect the result, so by keeping all other variables constant, we can ensure that only the manipulated variable will affect the result (state out the result).
Sample Answer: The location of the experimental set-up will also affect the amount of water left in the beaker, thus by placing both set-ups in the same location, it will ensure that the amount of water left in the beaker is solely affected by plant taking in the water and not due to other variables.