Question

electron configurations can be represented in an abbreviated form also known as the noble gas configuration for an element. what is the correct name and noble gas configuration for the element with the following configuration? 1s²2s²2p⁶3s²3p⁶4s²3d¹⁰4p⁶5s²4d² strontium - ar 5s24d2 strontium - kr 5s24d2 zirconium - kr5s24d2 zirconium - xe5s24d2

Explanation:

Step1: Calculate the total number of electrons

The sum of the exponents in the electron - configuration \(1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}4s^{2}3d^{10}4p^{6}5s^{2}4d^{2}\) is \(2 + 2+6 + 2+6 + 2+10 + 6+2 + 2=40\).

Step2: Determine the noble - gas core

The noble gas with an atomic number less than 40 is Krypton (\(Kr\), atomic number \(Z = 36\)).

Step3: Write the noble - gas configuration

The remaining electrons are \(40-36 = 4\). The electron configuration of the element is \([Kr]5s^{2}4d^{2}\).

Step4: Identify the element

Using the periodic table, the element with atomic number \(Z = 40\) is Zirconium (\(Zr\)).

Answer:

C. Zirconium - [Kr]5s24d2