Question

What element is represented by $1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}4s^{2}$

Answer 1

Answer: CALCIUM

EXPLANATION:

Add up all the electrons and the total number of electrons will be equal to the atomic number. If we know the atomic number we can quickly look at the periodic table and tell which element it is.

See the pics, the atomic number is 20 and it is Ca (CALCIUM)