Help! why are chemical equations always balanced?

C

Explanation:

The Law of Conservation of Mass states that matter cannot be created or destroyed and must be conserved. I is stating matter cannot be created, which is true. II is saying that matter can only be rearranged/conserved, which again is true. III states matter cannot be destroyed, which is also true. IV is incorrect because it doesn't make sense. Matter does matter.

periodic trends is an atom that gets larger as the number of electronic shells increase, the radius of atoms increases as you go down a certain group in the periodic table of elements. in general, the size of an atom will decrease as you move from left to right of a certain period.