Nonmetal

Some things are not metals.

These are called nonmetals. They can be gases or solids. Some can even be shiny!

They are often light. Most do not let heat or power move through them well. These things help make our air and water.

Two very light ones are part of almost everything in space. They are very important to our world.

Some elements are not metals. We call these nonmetals.

Nonmetals look very different from each other. Some are colorless gases, like hydrogen. Others are shiny crystals, like iodine.

Most nonmetals are light. They have low density, which means they do not weigh much for their size. Many are poor conductors. This means heat and electricity do not move through them easily. Some nonmetals are insulators. An insulator is a material that does not let electricity flow well.

Nonmetals are very important to our world. Five of them help make our air, oceans, and the ground. These are hydrogen, carbon, nitrogen, oxygen, and silicon.

Two nonmetals are very special. Hydrogen and helium are the lightest. Together, they make up about 98% of the mass in the known universe. This shows how much nonmetals matter to everything we see.

Nonmetals are a group of chemical elements that lack the typical traits of metals.

While metals are often shiny and easy to bend, nonmetals are very different. They can be colorless gases like hydrogen or shiny crystals like iodine.

Most nonmetals are also lighter than metals, which means they have a low density. Many of them are poor conductors. This means heat and electricity do not move through them easily. They can even act as insulators, which are materials that stop electricity from flowing.

These elements work in many different ways depending on how their atoms are held together. Some nonmetals exist as tiny, separate molecules, like oxygen or sulfur. These are often held together by weak forces, so they have low melting points. Other nonmetals form much larger structures. For example, carbon can form flat sheets in graphite or a 3D lattice in a diamond.

These larger structures make the nonmetal a solid with a much higher melting point. Some nonmetals, like boron or silicon, can even act as semiconductors. This means they can carry electricity better than a regular insulator.

Humans have known about the difference between metals and other minerals since ancient times. However, the specific way we group elements as metallic or nonmetallic only began in the late 18th century. Most of the nonmetallic elements we know today were identified during the 18th and 19th centuries. Scientists have suggested about twenty different ways to tell a nonmetal apart from a metal. Today, researchers often look at the electronic structure of the solid to make this choice. This helps them identify special cases like semimetals.

There are seventeen elements widely recognized as nonmetals.

Some scientists also include six borderline elements called metalloids in this group. These metalloids are intermediate, meaning they sit somewhere between metals and nonmetals. The two lightest nonmetals are hydrogen and helium. These two are incredibly important because they make up about 98% of the mass of the observable universe.

Other nonmetals like nitrogen and oxygen are also vital for life.

Nonmetals are part of almost everything you see around you. Five specific nonmetals—hydrogen, carbon, nitrogen, oxygen, and silicon—make up much of the Earth's atmosphere, oceans, and crust.

They are also used in many modern industries. You can find nonmetals used in electronics, lubrication, and even in machines. Even the air you breathe is made of these important elements. Without them, the Earth and the universe would look very different.

Nonmetals are a group of chemical elements that lack the distinctive properties typically associated with metals.

While metals are often shiny, malleable, and excellent conductors, nonmetals are much more diverse. They can appear as colorless gases, colored liquids, or shiny, brittle solids. This group is defined by what it lacks more than what it possesses. Because there is no single, universally accepted definition for all nonmetals, scientists often use a variety of criteria. These criteria include physical traits like density and appearance, or chemical traits like how they react with other elements.

To understand how nonmetals behave, we must look at their atomic structure and bonding. Many nonmetals exist as small, discrete molecules, such as oxygen or sulfur. These molecules are held together by weak London dispersion forces. Because these forces are weak, these elements often have low melting and boiling points. They frequently exist as gases at standard temperature and pressure. In contrast, some nonmetals form extended structures. Carbon can form flat sheets in graphite or a three-dimensional lattice in diamond. These large, interconnected structures result in much higher melting points and greater hardness.

Nonmetals also show a wide variety of physical appearances based on how they interact with light. Some, like hydrogen and nitrogen, are colorless because they do not absorb any visible light. Others, like chlorine, have distinct colors. Chlorine appears yellow-green because it absorbs light in the violet and blue regions of the spectrum. Some nonmetals can also appear shiny. Elements like iodine, boron, and silicon reflect incoming visible light, giving them a luster. Interestingly, nonmetals vary in their ability to conduct electricity. Most are insulators, which means they do not allow electricity to flow easily. However, some can act as semiconductors. Elements like silicon and germanium can change their conductivity when they are mixed with specific impurities, known as dopants.

Classification of these elements has changed as our scientific understanding has grown. Humans have distinguished metals from other minerals since antiquity. However, the specific classification of elements as metallic or nonmetallic only emerged in the late 18th century. Most nonmetallic elements were identified during the 18th and 19th centuries. Today, researchers often use the electronic structure of solids to define these groups. This modern approach helps identify complex cases like semimetals. For example, carbon, arsenic, and antimony are now often classified as semimetals, which are a specific subclass of metals.

There are seventeen elements widely recognized as nonmetals.

Additionally, six borderline elements known as metalloids are sometimes included in this group. Metalloids are intermediate elements that share properties with both metals and nonmetals. The two lightest nonmetals, hydrogen and helium, are incredibly significant on a cosmic scale. Together, they account for approximately 98% of the total mass of the observable universe.

On our own planet, five nonmetals are essential for life and structure. Hydrogen, carbon, nitrogen, oxygen, and silicon form the bulk of the Earth's atmosphere, biosphere, crust, and oceans.

Nonmetals are also known for their unique chemical reactivity. In chemical bonds, nonmetals often have high electronegativity. This means they have a strong tendency to attract electrons from other elements. Their oxides also tend to be acidic, which is a key difference from metal oxides that are often basic.

The diversity of nonmetals is also seen in their allotropes. An allotrope is a different physical form of the same element. For instance, carbon can exist as graphite or diamond. Nitrogen, oxygen, phosphorus, sulfur, selenium, and iodine also exhibit various allotropic forms with distinct properties.

Because of these unique traits, nonmetals are vital to modern technology and industry. They are the dominant components in many industrial processes. Nonmetals are used extensively in electronics, combustion, lubrication, and machining.

From the gases that make up our atmosphere to the semiconductors in our computers, nonmetals are fundamental to both the natural world and human innovation. They bridge the gap between the simple gases of space and the complex structures of life on Earth.