How does calcium obey the octet rule when reacting to form compounds?

a. it gains electrons.

b. it does not change its number of electrons.

c. it gives up electrons.

d. it fills its valence level.

e. it shares electrons.

Option (C) is the correct answer.

Explanation:

Atomic number of calcium is 20 and its electronic distribution is 2, 8, 8, 2.

Therefore, a calcium atom contains two valence electrons and in order to attain stability it needs to lose two electrons.

Hence, it acquires a charge of +2 as by loss of two electrons.

As, according to the octet rule there must be eight electrons in the valence shell.

Thus, we can conclude that calcium obey the octet rule when reacting to form compounds as gives up electrons.