The law of Lavoisier and Laplace illustrates

Options

A. The principle of conservation of energy
B. Equivalence of mechanical and thermal energy
C. The principle of conservation of matter
D. Equivalence of mechanical and chemical energy

Explanation

To solve the question regarding the law of Lavoisier and Laplace, we can break it down into the following steps:

### Step 1: Understand the Law of Lavoisier and Laplace
The law states that the energy change during a transformation is equal and opposite to the energy change during the reverse process. This means that energy is conserved in any chemical or physical transformation.

### Step 2: Relate to the Principle of Conservation of Energy
The principle of conservation of energy states that energy cannot be created or destroyed, only transformed from one form to another. This aligns perfectly with the law of Lavoisier and Laplace, as it emphasizes that the total energy in a closed system remains constant.

### Step 3: Identify the Correct Option
Given the context of the question, the law of Lavoisier and Laplace illustrates the principle of conservation of energy. Therefore, the correct answer is option A.

### Final Answer
The law of Lavoisier and Laplace illustrates the principle of conservation of energy.

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