The periodic table is called “periodic” because it is arranged to show repeating patterns. What is one of those repeating patterns?
A. atomic mass
B. atomic number
C. number of protons
D. number of valence electrons

Respuesta :

Answer:

A. atomic mass

Explanation:

Periodic Properties of the Elements Mendeleev saw that when the elements were arranged in order of increasing atomic mass, those that had similar properties occurred in a repeating pattern. That is, the pattern was periodic. Periodic means “happening at regular intervals.” Hope this helps!!

The answer is a. Atomic mass