Question

why must total mass logically stay the same in a chemical reaction according to your study guide?
if the number of reactants changes during a reaction no matter how those products are rearranged, their total atomic number must also stay the same.
if the number of atoms stays the same during a reaction no matter how those atoms are rearranged, their total mass must also stay the same.
if the number of valence electrons stays the same during a reaction no matter how those electrons are rearranged, their total viscosity must also stay the same.
if the number of elements stays the same during a reaction no matter how those elements are rearranged, their total luster must also stay the same.

Explanation:

In a chemical reaction, atoms are neither created nor destroyed. They are just rearranged. Since mass is associated with the number of atoms, if the number of atoms remains constant during a reaction regardless of rearrangement, the total mass must stay the same. This is based on the law of conservation of mass.

Answer:

If the number of atoms stays the same during a reaction no matter how those atoms are rearranged, their total mass must also stay the same.