What is Elements?
An element is a pure substance made up of one type of atom. Elements are the building blocks of all the rest of matter in the world. Examples of elements include iron, oxygen, hydrogen, gold, and helium.
Atomic Number
An important number in an element is the atomic number. It is the number of protons in each atom. Each element has a unique atomic number. Hydrogen is the first element and has one proton so it has an atomic number of 1. Gold has 79 protons in each atom and has an atomic number of 79. Elements in the standard state also have the same number of protons. electrons relative to the number of protons.
Forms of an Element
Even though elements are all made from the same kind of atoms, they can still come in different forms. Depending on their temperature they can be solid, liquid, or gas. They can also take different forms depending on how tightly the atoms are packed together. Scientists call these allotropes. One example of this is carbon. Depending on how the carbon atoms come together, they can form diamond, coal, or graphite.
How many elements are there?
There are currently 118 known elements. Of these, only 94 are thought to exist naturally on Earth.
Families of Elements
Elements are sometimes grouped together because they have similar properties. Here are some types:
Noble Gases – Helium, Neon, Argon, Krypton, Xenon and Radon are all noble gases. They are unique in that the outer shells of their atoms are filled with electrons. This means they don’t react much with other elements. They are often used in signs because they glow brightly when an electric current is passed through them.
Alkali Metals – These elements have only one electron in the outer shell of the atom and are highly reactive. Some examples are lithium, sodium, and potassium.
Other groups include transition metals, nonmetals, halogens, alkaline earth metals, actinides, and lanthanides.
Periodic Table
The periodic table is an important way to learn and understand chemical elements. You can read more about it on our Periodic Table of Elements page.
Fun Facts about Elements
The elements found on Earth and Mars are exactly the same.
Hydrogen is the most common element found in the universe. It is also the lightest element.
Isotopes are atoms of the same element with different numbers of neutrons.
In ancient times, the elements were called fire, earth, water, and air.
Helium is the second most abundant element in the universe, but it is very rare on Earth.