Question

Calcium has 20 electrons. how many electrons are in the outer shell?
a. 0
b. 2
c. 6
d. 8

Answer 1

Calcium is a metal found in the right side of the periodic table. It has 20 electrons which means the neutral atom has an atomic number of 20 as verified in the periodic table. It belongs to family with 2 valence electrons in its outer shell. Hence the charge of calcium is plus 2.

Answer 2

Answer:

2

Explanation:

For the first 20 elements, the first energy level can hold a maximum of two electrons, the second energy level can hold a maximum of 8 and the third energy level can hold a maximum of 8. Calcium has 20 electrons, so we put two in the first energy level, 8 in the second, 8 in the third and we are left with two for the fourth energy level.

Ca: 2,8,8,2