What Are Atoms? A Simple Explanation

The basics of atomic structure made simple.

Photo by Vedrana Filipović on Unsplash

British spelling.

Atoms consist of a nucleus at their centre, surrounded by varying numbers of electrons.

Apart from a hydrogen atom, the other 117 types of atom have nuclei containing different numbers of protons and neutrons. The number of protons and neutrons determines an atom’s mass.

An atom’s atomic number simply tells you how many protons are in its nucleus. Hydrogen, the lightest atom, has one proton, helium has two, and the numbers increase as you move through the Periodic Table.

The next few lines help to show just how much empty space there is inside an atom.

Imagine scaling up an atom so that its nucleus, the centre of the atom, is the size of a professional football, about 22 centimetres (8.7 inches) in diameter.

Astonishingly, on that scale, the outermost electrons (called valence electrons) could be as far as 5.5 kilometres (3.4 miles) from the nucleus, giving the atom a total diameter of about 11 kilometres (6.8 miles).

Now consider how many footballs would be needed to fill that enormous sphere. By volume, it would hold roughly 125 trillion footballs. Wow indeed!

Let’s start with the lightest atom and take a look at atoms in a simple way.

I’m a Hydrogen Atom (H) With Atomic Number 1

By far, I am the most abundant chemical element in the universe.

I am the oldest, lightest, and most abundant element in the universe, making up 74% of its mass.

I did not exist in the early universe because the conditions were too hot, but around 380,000 years after the universe’s birth, (the big bang) the cooler conditions enabled me to become a true atom.

My nucleus is just one proton, and one spinning electron circles my nucleus. That’s the reason I am the lightest of the 118 known elements.

Stellar nucleosynthesis is the process by which atoms are created within stars, intense heat in the core of stars triggers nuclear fusion starting the production of heavier atoms.

I’m a Helium Atom (He) With Atomic Number 2

I am the second most abundant chemical element in the universe.

Two electrons circle my nucleus, composed of two protons and two neutrons.

At this time, I am being created in the fiery cores of stars.

My age is slightly less than the most abundant chemical element, hydrogen, but I still make up 25% of all the mass in the universe.

Helium is known best for filling party balloons, but it has many other important uses, including medical technology, scientific research, and space exploration.

Being so light means that some helium can escape into space and because of its chemical composition, it’s impossible to produce helium artificially.

I’m a Lithium Atom (Li) With Atomic Number 3

I, hydrogen and helium came into existence just after the universe’s birth.

At the beginning of the universe, hydrogen and helium contributed up to 99% of its mass; my contribution was a mere 1%.

Having three protons and four neutrons in my nucleus makes me heavier than hydrogen and helium atoms.

At room temperature, my state is a solid, soft alkali metal.

Room temperature can be described as 20–22 degrees Celsius or 68–72 degrees Fahrenheit.

Lithium has many uses, including heat-resistant glass and ceramics, flux additives for iron and steel, and aluminium production.

Lithium is also associated with batteries. Lithium metal and lithium-ion batteries use a large percentage of the total production of lithium, and the demand keeps growing.

The Earth has approximately 88 million metric tonnes of lithium that can be mined.

I’m a Beryllium Atom (Be) With Atomic Number 4

I wasn’t around at the beginning of the universe.

Two chemical elements dominated the early universe: hydrogen and helium.

I’m a solid metal at room temperature, stronger than steel and lighter than aluminium, but harmful to humans if inhaled.

Beryllium is rare in the universe, contributing only 1%.

There were no stars in the early universe; millions of years after the Big Bang, hydrogen and helium came together in massive clouds, forming the first stars.

Cosmic ray fission was responsible for the creation of beryllium.

Because of its strength, lightness, and resistance to extreme temperatures, beryllium was chosen to construct the primary mirror on the James Webb Space Telescope.

I’m a Boron Atom (B) With Atomic Number 5

Regarding mass, how abundant am I in the universe? The answer is 0.0001% or one ten-thousandth of 1%.

I wasn’t created in stars but in high-speed cosmic ray collisions (fission). Nuclei can be fragmented through spallation, and the outcome can be elements such as me.

At room temperature, I am a solid.

Cosmic rays are high-energy particles travelling through space.

A boron atom contains five protons, six neutrons, and five electrons.

Boron is an important structural component of plants. It is required for plant growth, seed formation, and pollination.

Without plants, we would not exist. Although boron is scarce in the universe, its importance on Earth cannot be underrated.

Boron is used in the manufacturing of glass and ceramics, fertilisers, detergents, and bleaches.

If you’d like to explore my simple explanation of atoms a little further, please follow the link. I hope you find them both interesting and educational!

[embed]I’m a Carbon Atom (C) With Atomic Number 6 Among all the chemical elements, I consider myself very important.medium.com