is oxygen a metal nonmetal or metalloid

Is oxygen a metal nonmetal or metalloid? Learning about how you classify oxygen will help you understand more about its chemical properties.

Essentially, a metal is shiny, hard, ductile, and a good conductor of heat, whereas a nonmetal lacks these qualities.

And metalloid usually has mixed properties of nonmetals and metals.

But, the question is, “is oxygen a metal or nonmetal or metalloid?”

Oxygen is nonmetal mainly because it is not a good conductor of heat or electricity and does not produce a strong reflection of light. 

The All-Important Oxygen

view from below the trees

Oxygen is essential to the survival of nearly all forms of life on Earth.

There is more of this element in our bodies than any other, and it is the third most common element in the universe.

Speaking of its chemical makeup, you will find 8 protons and 8 electrons in oxygen. You can find it in the periodic table, way up at the top of column 16.

Fact: Because of their high thermal and electrical conductivity, metals are used to construct cutlery, electrical cables, and home appliances. 

Basic Properties of Oxygen

Denoted as O2, oxygen consists of pairs of atoms, or molecules, at room temperature and pressure.

In the scientific world, it is classified as a diatomic gas. Oxygen in this state is a tasteless, odorless, and colorless gas.

human  crown forming oxygen symbol

When discussing oxygen, you just cannot ignore talking about ozone, which is so close to oxygen yet different.

Ozone is an allotrope of oxygen (O3). The ozone layer, composed of ozone gas, shields Earth’s surface from the sun’s ultraviolet radiation.

It is worth mentioning that pure oxygen is extremely reactive, combining with a wide variety of other elements to form compounds.

But, to learn more about its properties, it is essential to know “Is oxygen a metal metalloid or nonmetal?” 

Is Oxygen a Metal Nonmetal or Metalloid?

sunset and colorful hot air balloon

Oxygen is a nonmetal.

For a chemical to be classed as nonmetal it also has to be a poor conductor of heat and electricity. 

And it should have a structure that is neither malleable nor ductile. That is to say, it is brittle and can’t be hammered into a sheet or pulled through a cable. 

Chemicals in the nonmetal group can have other properties too;

  • Most nonmetals readily form compounds with other chemicals
  • They usually gain electrons during reactions with metals forming negative ions
  • Nonmetals share electrons with other nonmetals in a process called covalent bonding.
Fact: Aluminum is a good example of metal, which is used for storage and transport packaging, and is also put to use in airplanes and cars. 

Oxygen as a Nonmetal

To understand why oxygen is a nonmetal, it is necessary to define the difference between nonmetals, metalloids and metals as they are represented on the periodic table.

a warehouse of oxygen cylinder

The periodic table organizes chemicals by their atomic number. Oxygen has an atomic number of 8. This means each oxygen molecule has 8 protons.

Because of its atomic number, that is, the number of its protons, oxygen is grouped with similar chemicals to form groups 14 through 18 on the left of the table.

The chemicals represented around it are also poor electricity and heat conductors and like oxygen, are nonmetal.

Including oxygen, there are 17 nonmetal elements forming their own subset of nonmetals.

Some of them include:

  • Hydrogen
  • Fluorine
  • Carbon
  • Chlorine
  • Sulfur
  • Helium
  • Bromine

All the known chemicals, including the elements like oxygen, have been organized onto the table this way, by their atomic number and its properties. 

Understanding The Concept of Metalloids

Oxygen is not a member of the group of metalloids because its properties are discrete and different. 

rough antimony ore stone

However, it is important to know that chemicals in the metalloid group share some of the properties of the chemicals in both the nonmetal and metal groups.

These include:

  • being solid at room temperature
  • being hard and brittle
  • being reactive
  • being shiny

There are seven metalloids, which are also called semimetals, but they form a versatile group of chemicals.

They are:

  • Boron, used to harden glass and steel and added to fertilizer as an insecticide.
  • Arsenic, toxic and added to alloys as a hardener and used as a wood preserver.
  • Silicon, found in rock and sand, used in manufacturing alloys, ceramics, and enamels.
  • Antimony, used in semiconductors, paint, alloys, glass, enamel and ceramics.
  • Polonium, used to remove static electricity, and as a heat source in space satellites.
  • Tellurium, very rare, used in alloys to make them stronger and resistant to corrosion.
  • Germanium, used as an additive to improve corrosion resistance, used in infrared conductors and semiconductors.

All seven of the metalloid chemicals are solids, whereas oxygen, if left in its natural state is a gas. Therefore, oxygen is not semimetal.

Fact: Non-metal elements like phosphorus and nitrogen are used in fertilizers to increase crop output. 

Deciding If Oxygen Is Metal, Metalloid or Nonmetal

By understanding the properties of metals, metalloids and nonmetals we are able to sort and classify them.

The Periodic Table is a way to display each chemical so that it groups with other chemicals with shared properties.

magnifying glass and periodic table

Since both the metalloid and metal chemicals are solids, with the exception of mercury and oxygen is not, oxygen can not be in either group.

Even though some nonmetals can be solids, the gas, oxygen must be a nonmetal.

Another property of the metals and the semimetals is that they appear shiny, they have a luster. Oxygen being a colorless gas, does not.

As a nonmental, oxygen, like the other chemicals in the group, readily reacts with other chemicals and gains electrons when reacting with the metals, to form ionic compounds.

These are made of negatively and positively charged ions that form a lattice. It is this lattice that gives a nonmetal compound its properties.

The lattice:

  • Forms crystals.
  • Is hard and brittle.
  • Conducts electricity.
  • Is a good insulator.
  • Has a high melting point.

An example of an ionic compound is salt. Like oxygen, salt is a nonmetal substance. 

Can Oxygen Be a Metal?

alkali metal

Since oxygen is not a metalloid, can it be metal? The metals occupy much of the left-hand side of the table.

Along the horizontal, they group into:

  • Alkali metals group 1
  • Alkaline earth metals
  • Group 2 and the transition metals
  • Groups 3 to 12

The number of the group reflects the number of electrons each chemical has. 

Alkali Metals Group 1

The alkali metals with one electron are caesium, rubidium, potassium, lithium, and francium.

The metals in this group are very reactive and explosive when they come into contact with air, which contains oxygen. They form a metal oxide.

If they react with oxygen in water, they form a metal hydroxide. Due to their reactive nature, they are not found in pure in nature whereas oxygen is. 

The Alkaline Earth Metals

The group includes:

  • Radium
  • Calcium
  • Beryllium
  • Strontium
  • Magnesium
  • Barium

These too are very reactive and therefore not found in their pure states in nature. Being in group 2, they each have 2 electrons.

Fact: Non-metal like carbon is effective as fuel, whereas chlorine helps with the water purification process. 

The Transition Metals

Group 3, the transition metals apart from mercury, each chemical in the metals is shiny in appearance. Oxygen does not belong to this group either.

illustration of transition metals

Metals are solids, unlike oxygen and also have high melting points. A sub-group of metal chemicals have lower melting points, but relatively speaking they are still high.

They occupy columns 3 to 12 of the periodic table and include the metals we are most familiar with, gold, silver, copper, platinum, nickel and titanium for example. 

Post-transition Metals, Lanthanoids and Actinoids

The metals with lower melting points are called post-transition metals.

They are:

  • Bismuth
  • Aluminium
  • Indium
  • Thallium
  • Gallium
  • Lead

The remainder of the transition metals falls into two groups, lanthanoids and actinoids.

Lanthanoids have atomic numbers between 57 and 71. They are the metals found in compounds formed in the earth’s crust and therefore solids. Some react with air to tarnish.

Actinoids have atomic numbers from 89 to 103. They are mainly man-made and radioactive. They too are solids. 


view from above of two oxygen cylinder

Is oxygen a metal nonmetal or metalloid? Considering the properties of nonmetal, metal, and metalloid, it is clear that oxygen is a nonmetal.

The oxygen atom is quite small and it has a high electronegativity. Also, it does not belong in the metal family, making it a strong non-metal.