Which process involves a chemical change?
AButter melts on warm toast
BWater evaporates from a surface
CJuice in a bottle freezes solid
DFood scraps turn into compost
Answer & Solution
Correct answer: D. Food scraps turn into compost
1. A chemical change forms a new substance and cannot simply be reversed.
2. Food scraps decomposing into compost produce entirely new substances, so that is chemical.
3. Butter melting only changes state, and the liquid can freeze back to solid.
4. Evaporation and freezing are likewise reversible changes of state.
5. Drying a wet cloth only evaporates water, forming no new substance at all.
_Source: NECTA CSEE 2021 Chemistry 032, Question 1: Multiple Choice, item (iii)_
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