According to the Law of Conservation of Mass, what should the total mass of the jar and its contents be after the candle goes out in a closed system?

• A. The total mass should decrease because the candle burned.
• B. The total mass should fluctuate depending on the amount of oxygen consumed.
• C. The total mass should increase due to the production of gases.
• D. The total mass should remain the same as it was before the candle was lit.

Answer: (D)

Verified step by step guidance

1. Recall the Law of Conservation of Mass, which states that mass cannot be created or destroyed in a closed system during a chemical reaction.
2. Understand that when the candle burns, it undergoes a chemical reaction (combustion) where the wax reacts with oxygen to form new substances like carbon dioxide and water vapor.
3. Since the system is closed, no matter (mass) can enter or leave the jar, so all reactants and products remain inside the jar.
4. Therefore, even though the candle burns and changes form, the total mass of the jar and its contents must remain constant throughout the process.
5. Conclude that the total mass after the candle goes out will be the same as the total mass before the candle was lit.