The Atom

Introduction

This article discusses the atom, its sub-atomic particles, the nucleus, the atomic structure of an element, the shells and valence shells, the lost and gain of electrons, the octet rule, what is a positive, negative, and neutral atom, what a molecule is, what a compound is, the main types of bonds, isotopes, isotones, what nuclear energy is, and fusion and fission of an atom.

WHAT IS AN ATOM

It is defined as the smallest particle of an element that can take part in a chemical reaction. The atomic structure of an element is represented in cycles called shells; the number of electrons arranged in the shell(s) of an atom obeys a rule called the octet rule. The middle section of an atom is called the nucleus, it contains two sub-atomic particles- the proton and neutron.

Sub-Atomic Particles

There are three different types of sub-atomic particles: The proton and neutron located in the nucleus of the atom and electrons which are found around the space of the nucleus.

Three Sub-Atomic Particles:

The proton: It is a positively charged particle found in the nucleus of an atom (+).

The neutron is a particle with no charge (0).

The electron: It is a negatively charged particle located around the nucleus of an atom in an open space (-).

A neutral atom is an atom that has not lost or gained an electron; for an atom to become stable, it loses or gains one or more electrons in its valence shell. When an atom loses one or more electron(s), it becomes positively charged and negatively charged when it gains one or more electron(s).

The shell

It is an imaginary space around the nucleus of atoms where electrons obit. They are represented in circles around the nucleus; the first shell starts from the nucleus, followed by the second, and so forth. Each circle represents an energy level; the number of electrons in a shell obeys a rule called the octet rule which is two times “n” raised to the power two (2n^2). In this formula, the first 2 is the constant, “n” represents the number of shells that electrons have to fill- the first shell is located right after the nucleus followed by the second, third, etc. - and “n” is raised to the power 2.

Valence Shell

The valence shell of an atomic structure is the outermost shell of the atom’s electronic configuration. The number of electrons located in a valance shell determines whether the atom is positive, negative, or stable; atoms lose or gain electrons in their valance shells to obey the octet rule.

The Octet Rule

The octet rule is a rule that is used to determine the maximum number of electrons that are to occupy the shells of atoms. For example, from the formula 2n^2, if “n” is the 3rd shell from the nucleus of the atom, the number of electrons that would occupy the third shell is 2(3)^2; that is, 3 raised to the power 2 all multiplied by 2 which is 2x(3)^2, 2x9 which equals 18.

What Is a Molecule

A molecule is a group of atoms from the same element or different elements chemically combined and can take part in a chemical reaction.

Examples of molecules:

Molecule of the same element: N2 (Nitrogen).

Molecule of different elements: CaO (Calcium oxide).

Molecule of two or more elements: C6H12O6 (Glucose).

What Is a Compound

A compound is a substance made of elements chemically combined in a fixed ratio; the bonds formed between elements in a compound are strong and are difficult to break.

Type Of Bonds

A bond is when substances come together to form a substance. There are two main types of bonds, namely, Ionic and Covalent bonds.

Ionic Bonds

They are bonds that are formed when metal atoms and nonmetal atoms combine by exchanging their valence electron(s) to become stable. Between covalent and Ionic bonds, Ionic bonds are the weakest because, instead of sharing the electrons within their valence shells, they exchange them. Examples of ionic bonds are Sodium Chloride, Na+ and Cl- (NaCl), magnesium+2 and sulphate2- (MgSO4), and sodium bicarbonate (NaHCO3).

Covalent Bonds

This is the type of bond formed when two nonmetals share pair(s) of valence electron(s) to become stable; it is the strongest type of bond between the two. Examples of covalent bonds are Hydrogen Chloride (HCl), Water (H2O), CO2, etc.

Isotopes and Isotones

What Is an Isotope: It is a group of atoms of the same element, they have the same atomic number (protons) but different mass numbers due to the differences in the number of neutrons. For example, the isotopes of hydrogen, have three different types of isotopes with three different mass numbers but the same atomic number due to the same number of protons but different numbers of neutrons.

Isotones: they are atoms with the same number of neutrons but different atomic numbers due to the differences in the number of protons. Examples of isotones are Chlorine and Potassium; Chlorine has an atomic number of 17 and a neutron number of 20 whereas Potassium has an atomic number of 19 and a neutron number of 20.

What is Nuclear Energy

Nuclear Energy: It is the energy derived by nuclei of atoms in a controlled environment called nuclear reactors; energy derived is mostly used for electricity. Energy derived by fission or fusion of nuclei is used to heat water; steam generated from heated water is used to turn turbines of generators to generate electricity.

Fission: It is the splitting of nuclei of atoms in a controlled environment to produce a large sum of energy; energy derived from nuclei fission is used to heat water, and steam produced from heated water is used to turn turbines of generators to generate electricity. The energy produced can be used to power ships, submarines, generators to produce electricity, etc.

Fusion: It is the joining of atomic nuclei with low atomic numbers in a controlled environment to generate energy which is used to heat water producing steam to turn turbines of generators thereby producing electricity. The energy produced can be used to power ships, submarines, generators to produce electricity, etc.

The world of atoms is fascinating; you sitting, standing, lying down, walking, running, etc. are made of atoms. It is the building block of every matter; atoms are so small that they cannot be seen with the naked eye. The diameter of an atom is approximately 0.1 – 0.5 nanometers; there are about 10^23 atoms in one gram of matter. To get a glimpse of how powerful a nuclear chain reaction is, take a look at the destructive power of the atomic bomb dropped on Hiroshima and Nagasaki which led to the end of World War II. Today, there are atomic bombs that are more than 10x powerful than the two dropped during World War II; Albert Einstein was then right to call for the ban of the use of atomic weapons. If it might interest you, his famous equation E= mc^2 led to the creation of the first atomic weapon. With this, I end this article with a statement that, “I stand with Albert”!

Author: Sekou Sesay