The number 40 in the name calcium-40 represents

A. the atomic number

B. the number of protons in the atom

C. the sum of the protons and neutrons

D. none of these

A. the atomic number

Explanation:

It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth.

because u need two or more forms of the same element that contain equal numbers of protons but different numbers of neutrons in their nuclei to form isotopes.

so since they all have the same shape? i mean maybe because m& m and reeses are both chocolates