Question
What happens when a candle is burnt? Explain the physical and chemical changes involved.
✓
Answer
Burning a candle involves both physical and chemical changes.
→ Physically, the wax melts (state change) due to the heat, and this melted wax can solidify again if cooled.
→ Chemically, the wax undergoes combustion, reacting with oxygen to produce carbon dioxide and water vapor (new substances), releasing heat and light. This combustion is irreversible.
→ Physically, the wax melts (state change) due to the heat, and this melted wax can solidify again if cooled.
→ Chemically, the wax undergoes combustion, reacting with oxygen to produce carbon dioxide and water vapor (new substances), releasing heat and light. This combustion is irreversible.
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