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Question
State whether the following statement is true or false:
When a candle burns, both physical and chemical changes take place.
Options
True
False
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Solution
This statement is True.
Explanation:
When a candle burns, both physical and chemical changes occur:
-
Physical Change: The wax of the candle melts due to the heat of the flame. This is a reversible change as the wax can solidify again when cooled.
-
Chemical Change: The wax undergoes combustion, reacting with oxygen in the air to form carbon dioxide and water vapour. This is an irreversible chemical reaction.
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