EVERYDAY SCIENCE

Detailed explanation-1: -The law of conservation of mass states that in a chemical reaction mass is neither created nor destroyed. For example, the carbon atom in coal becomes carbon dioxide when it is burned. The carbon atom changes from a solid structure to a gas but its mass does not change.

Detailed explanation-2: -The Law of Conservation of Mass dates from Antoine Lavoisier’s 1789 discovery that mass is neither created nor destroyed in chemical reactions. In other words, the mass of any one element at the beginning of a reaction will equal the mass of that element at the end of the reaction.

Detailed explanation-3: -Mass is therefore never conserved because a little of it turns into energy (or a little energy turns into mass) in every reaction. But mass+energy is always conserved. Energy cannot be created out of nothing. It can only be created by destroying the appropriate amount of mass according to E = mc2.

Detailed explanation-4: -A given compound always contains exactly the same proportion of elements by weight can be explained by the Law of Constant Proportion. Hence this is an incorrect statement about the Law of Conservation of Mass.

Detailed explanation-5: -Mass is always conserved in a chemical reaction because mass can neither be created nor be destroyed (law of conservation of mass).