Which of the following statements is true about the law of conservation of mass?

The law of conservation of mass states that mass cannot be created or destroyed in an isolated system. This means that the total mass of the reactants in a chemical reaction will always equal the total mass of the products. In other words, during any physical or chemical change, the mass of the substances involved will remain constant, ensuring that matter is conserved.

To clarify further, consider a closed system where a chemical reaction occurs. Regardless of the processes that take place within that system, the overall mass before the reaction must equal the overall mass after the reaction. This principle is foundational in chemistry and helps scientists understand the relationships between reactants and products in various types of reactions.

Additionally, it highlights the importance of balancing chemical equations, where the number of atoms for each element must remain the same on both sides of the equation, reflecting the conservation of mass. Thus, when analyzing questions about chemical reactions or physical changes, always remember that mass is preserved throughout.