Reading about Energy Critical Elements (or ECEs) the other day, the Clear Science Staff found ourselves thinking of this plot of elemental abundance in the Earth’s crust. The data comes from this US Geological Survey website. This can give you a good idea of how easy certain elements are to come by. The most common are oxygen (O) and silicon (Si), otherwise known as sand or glass when you put them together (silica SiO2).
Precious metals like platinum (Pt), gold (Au), and osmium (Os) are in the group of lowest occurrence. Rare earths are labeled in blue, and you can easily see they are not the most common but also not the rarest elements. However, this numerical “abundance” is only part of the story. There are other considerations when deciding how easy an element is to come by …  

Reading about Energy Critical Elements (or ECEs) the other day, the Clear Science Staff found ourselves thinking of this plot of elemental abundance in the Earth’s crust. The data comes from this US Geological Survey website. This can give you a good idea of how easy certain elements are to come by. The most common are oxygen (O) and silicon (Si), otherwise known as sand or glass when you put them together (silica SiO2).

Precious metals like platinum (Pt), gold (Au), and osmium (Os) are in the group of lowest occurrence. Rare earths are labeled in blue, and you can easily see they are not the most common but also not the rarest elements. However, this numerical “abundance” is only part of the story. There are other considerations when deciding how easy an element is to come by …  

We saw that at the beginning of the universe, the only elements present were the most simple ones: Hydrogen, Helium, and some Lithium and Beryllium.
Over billions of years, nuclear reactions in stars made heavier elements. Some of those include Carbon, Nitrogen, and Oxygen. These elements make up most of life on Earth.
They came from stars, and ended up here. They became part of the cycle of life. Some of them became you. You are made of star stuff.

We saw that at the beginning of the universe, the only elements present were the most simple ones: Hydrogen, Helium, and some Lithium and Beryllium.

Over billions of years, nuclear reactions in stars made heavier elements. Some of those include Carbon, Nitrogen, and Oxygen. These elements make up most of life on Earth.

They came from stars, and ended up here. They became part of the cycle of life. Some of them became you. You are made of star stuff.

You are made of elements, along with everything else on Earth. You’re mostly oxygen, carbon, hydrogen, and nitrogen.
However, on all of Earth, it’s a bit different. Oxygen is still #1, followed by silicon, aluminum, and iron.
Let’s be more extreme, and think bigger: in the cosmos, it looks very different. Hydrogen is by far the most abundant element, followed by helium. Everything else is only a very tiny fraction.
Remember: Life is part of the Earth, and the Earth is part of the universe. Carbon, for example, is very concentrated in living things on Earth, but is (in the grand scheme of things) a very rare thing.  

You are made of elements, along with everything else on Earth. You’re mostly oxygen, carbon, hydrogen, and nitrogen.

However, on all of Earth, it’s a bit different. Oxygen is still #1, followed by silicon, aluminum, and iron.

Let’s be more extreme, and think bigger: in the cosmos, it looks very different. Hydrogen is by far the most abundant element, followed by helium. Everything else is only a very tiny fraction.

Remember: Life is part of the Earth, and the Earth is part of the universe. Carbon, for example, is very concentrated in living things on Earth, but is (in the grand scheme of things) a very rare thing.  

But where does the name “Periodic Table” come from?
It’s “periodic” because elements have properties that recur in regular intervals as you add protons. The table is written so these elements fall in columns or groups.
There are several ways to name groups. For example with
names (“Alkali Metals” for example)
roman numerals and letters (“IA”)
a simple number (“Group 1”)
You may see all 3 of these at different times, but the concept is the same: The group belongs together.

But where does the name “Periodic Table” come from?

It’s “periodic” because elements have properties that recur in regular intervals as you add protons. The table is written so these elements fall in columns or groups.

There are several ways to name groups. For example with

  • names (“Alkali Metals” for example)
  • roman numerals and letters (“IA”)
  • a simple number (“Group 1”)

You may see all 3 of these at different times, but the concept is the same: The group belongs together.

The number of protons in the nucleus determines what element the atom is. Many atoms together, if they are the same element, make something you recognize. For example, lithium, sulfur, or osmium.

The number of protons in the nucleus determines what element the atom is. Many atoms together, if they are the same element, make something you recognize. For example, lithium, sulfur, or osmium.