How many electrons will an element have if it has an atomic number of 20, an atomic mass of 40 and a charge of +2? *
A.)40
B.)18
C.)22
D.)20

B)18
This is because the atomic number is the amount of protons. The number of protons equal the number of electrons in a neutral atom. But since it has a charge of +2, you subtract 2 from 20. +2 is a anion.

C. 1s22s22p63s23p43d104s24p5