Question

what element has the configuration $1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}4s^{2}3d^{2}$

Explanation:

Step1: Calculate the total number of electrons

The sum of the exponents in the electron - configuration gives the number of electrons.

$$2 + 2+6 + 2+6 + 2+6=26$$

Step2: Determine the element based on the atomic number

In a neutral atom, the number of electrons is equal to the atomic number. The element with atomic number \(Z = 26\) is iron (\(Fe\)).

Answer:

Iron (\(Fe\))