Which quantity or quantities must always be the same on both sides of a chemical equation? check all that apply. check all that apply. the number of atoms of each kind the number of moles of each kind of molecule the sum of the masses of all substances involved the number of molecules of each kind?

- The number of atoms of each kind.

- The sum of the masses of all substances involved.

Explanation:

Hello,

Chemical reactions are chemical processes wherein a series of reactants undergo a change in their composition due to a bond breaking caused by energetic means. In this manner, such change is constricted by two conditions which must be assured after the chemical reactions, they are:

- The number of atoms of each kind.

- The sum of the masses of all substances involved.

They are based on the law of conservation of mass which states that the mass can not be neither created nor destroyed, thus, the number of atoms of each kind and the sum of the masses must remain equal before and after the chemical reaction. For instance, consider the reaction:

Whereas the stoichiometric coefficients guarantees the first condition and the complete consumption-production the second one.

Best regards.

the answer is 75.0%.