While burning coal and charcoal, you notice that coal releases more heat than charcoal. What does that mean? A. The elastic energy is lower in charcoal than in coal.
B. The chemical potential energy is lower in charcoal than in coal.
C. The chemical potential energy is higher in charcoal than in coal.
D. The elastic energy is higher in charcoal than in coal.

The fact that coal releases more heat than charcoal means that the chemical potential energy is lower in charcoal than in coal.

When the substance is burnt in oxygen, the chemical potential energy stored in the substance is converted into heat energy. The substance that has the most chemical potential energy releases the most energy when burnt.

In burning coal and charcoal, you notice that coal releases more heat energy than charcoal. This means that the chemical potential energy is lower in charcoal than in coal.

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your parents i think this could be it

the product of the pressure and volume is also constant