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Question
State one instance where water undergoes a physical change and one in which it undergoes a chemical change.
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Solution
Water undergoes a physical change when it is heated to a temperature of 100°C. At this temperature, the water gets converted to water vapours. This process is called evaporation. Water undergoes a chemical change when it is subjected to electricity. It splits into its constituents, oxygen and hydrogen, by the process of electrolysis.
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