Chapter 2.1, Problem 1TYK

Summary Introduction

Introduction:

Periodic table is the arrangement of elements according to their atomic number, electron configuration. There is a periodic arrangement of chemical properties of the elements in the periodic table. Chemical element is a substance that cannot be decomposed into simpler substances by ordinary chemical processes. Inside an atom there is a nucleus and it contains protons and neutrons in it as subatomic particles. Nucleus is surrounded by a cloud of electrons. Atomic number of an element is always similar to the number of protons inside the nucleus.

Electron shells are the energy levels that have the ability to hold up the electrons. Electron shells consist with one or more electron subshells.