Question

The law of Lavoisier and Laplace illustrates
(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

Answer 1

Hint: Lavoisier was a French chemist who influenced the history of chemistry. He is known as the father of modern chemistry. He identified the element oxygen and also identified the stoichiometry of hydrogen.

Complete answer:
Lavoisier and Laplace law states that the energy change accompanying any transformation is equal and opposite to energy change accompanying the reverse process.
The law illustrates the law of conservation of energy states that energy can neither be created nor be destroyed it can only be changed from one form to another. It also illustrates the law of conservation of mass which states that the mass in an isolated system can neither be created nor be destroyed; it can only be changed from one form to another.
The law of conservation was given by Lavoisier and Laplace in the year 1789.

Hence the correct answer is option (A) i.e. The law of Lavoisier and Laplace illustrates the principle of conservation of energy.

Additional information:
The concept of law of conservation of mass and energy is widely used in chemistry, mechanics and in fluids as well. The law of conservation of mass helps to calculate the unknown mass, such as the amount of gas consumed or produced during a reaction.

Note:
Lavoisier and Laplace was the first to classify the then known elements into the metals and non metals. Students can get confused between Lavoisier and Gebler who was also referred to as the father of chemistry but he was a ninth century chemist.