Chapter 11, Problem 49E

Interpretation Introduction

Interpretation:

The electron configurations of chromium and selenium are to be stated.

Concept introduction:

Electronic configuration represents the arrangement of electrons in an atom. The sublevels are filled according to their increasing energy. The electrons are firstly filled into the sublevel having lowest energy. The sublevel closest to the nucleus has the lowest energy. The trend of filling of electrons according to the energy of sublevels is given below.

$1s<2s<2p<3s<3p<4s<3d<4p<5s<4d<5p<6s$

The electronic configuration up to the electronic configuration of the last noble gas is represented with the symbol of noble gas in square brackets. This notation is known as core notation.