What occurs during a chemical reaction?

During a chemical reaction, the process involves breaking the bonds between atoms in the reactants, which allows for the rearrangement of atoms to form new bonds in the products. This transformation is fundamental to chemical reactions, as it alters the identity of the substances involved.

The breaking and forming of bonds results in changes to chemical compounds, leading to the creation of new substances with different properties from the original reactants. This process is governed by the law of conservation of mass, which states that the total mass of the reactants is equal to the total mass of the products. Therefore, no mass is lost or gained; it is simply transformed as the reactants are converted into products through the reorganization of atoms.

The other choices misrepresent the nature of chemical reactions. For example, energy can be absorbed or released during a reaction, and new bonds are indeed formed. Additionally, chemical reactions involve the creation of new substances and not just a change in state. Finally, the total mass does not decrease; it remains constant throughout the reaction.