What Are The Nonmetals In The Periodic Table?

What are Nonmetals?

In chemistry, a nonmetal is a chemical element that generally lacks a predominance of metallic properties; they range from colorless gases to shiny and refractory (high melting point) solids. The electrons in nonmetals behave differently from those in metals.

With some exceptions, those in nonmetals are fixed in place, resulting in nonmetals usually being poor conductors of heat and electricity and brittle or crumbly when solid.

The electrons in metals are generally free moving and this is why metals are good conductors and most are easily flattened into sheets and drawn into wires. Nonmetal atoms are moderate to highly electronegative; they tend to attract electrons in chemical reactions and form acidic compounds.

Two nonmetals, hydrogen, and helium make up about 99% of ordinary matter in the observable universe by mass. Five nonmetallic elements, hydrogen, carbon, nitrogen, oxygen, and silicon, largely make up the Earth’s crust, atmosphere, oceans, and biosphere.

Most nonmetals have biological, technological, or domestic roles or use. Living organisms are composed almost entirely of nonmetal hydrogen, oxygen, carbon, and nitrogen. Nearly all nonmetals have individual uses in medicine and pharmaceuticals; lasers and lighting; and household items.

what are the nonmetals in the periodic table?

The metals are to the left of the line (except for hydrogen, which is a nonmetal located on the left top corner), the nonmetals are to the right of the line, and the elements immediately adjacent to the line are the metalloids.

nonmetals in periodic table

Nonmetals have high ionization energies and high electron affinities, so they gain electrons relatively easily and lose them with difficulty. They also have a larger number of valence electrons and are already close to having a complete octet of eight electrons. 

The nonmetals gain electrons until they have the same number of electrons as the nearest noble gas (Group 8A), forming negatively charged anions that have charges that are the group number minus eight.

That is, the Group 7A nonmetals form 1- charges, the Group 6A nonmetals form 2- charges and the Group 5A metals form 3- charges. The Group 8A elements already have eight electrons in their valence shells, have little tendency to either gain or lose electrons, and do not readily form ionic or molecular compounds.

Ionic compounds are held together in a regular array called a crystal lattice by the attractive forces between the oppositely charged cations and anions. These attractive forces are very strong, and most ionic compounds, therefore, have very high melting points. For instance, sodium chloride, NaCl, melts at 801°C, while aluminum oxide, Al2O3, melts at 2054°C.

Ionic compounds are typically hard, rigid, and brittle. Ionic compounds do not conduct electricity, because the ions are not free to move in the solid phase, but ionic compounds can conduct electricity when they are dissolved in water.

When nonmetals combine with other nonmetals, they tend to share electrons in covalent bonds instead of forming ions, resulting in the formation of neutral molecules. Keep in mind that since hydrogen is also a nonmetal, the combination of hydrogen with another nonmetal will also produce a covalent bond.

Molecular compounds can be gases, liquids, or low melting point solids, and comprise a wide variety of substances.

List of nonmetals on the Periodic table

Here is a complete list of all the 18 nonmetals on the Periodic table.

Atomic numberSymbolName of element
1HHydrogen
2HeHelium
6CCarbon
7NNitrogen
8OOxygen
9FFluorine
10NeNeon
15PPhosphorus
16SSulfur
17ClChlorine
18ArArgon
34SeSelenium
35BrBromine
36KrKrypton
53IIodine
54XeXenon
85AtAstatine
86RnRadon

Properties of Nonmetals

In general, non-metals are brittle, dull, and have poor conductors of heat and electricity. They tend to have lower melting points than metals. Most of the nonmetals exist in two of the three states of matter at room temperature: gases and solids, except bromine, which exists as a liquid.

Nonmetals have high ionization energies and electronegativities. Most nonmetals have the ability to gain electrons easily. Nonmetals display a wide range of chemical properties and reactivities.

Physical Properties of Nonmetals

The following are the properties of Nonmetals:

  • Nonmetals have high ionization energies.
  • They have high electronegativities.
  • Nonmetals are insulators which means that they’re poor conductors of electricity.
  • They are dull, they do not have luster like metals.
  • Nonmetals are poor conductors of heat. They’re poor thermal conductors.
  • They are very weak and brittle. They tend to easily break or shatter.
  • Nonmetals have a low density. They’re light for their size.
  • They aren’t good conductors of sound and do not make sounds when they are hit.
  • They tend to gain electrons easily.
  • Nonmetals may be solids, liquids, or gaseous.
  • Nonmetals form acidic oxides.
  • They’re good oxidizing agents.
  • Generally, Nonmetals have four to eight electrons in the outer shell.

Chemical Properties of Nonmetals

The chemical properties of nonmetals:

  • Nonmetals are poor conductors of heat and electricity. Graphite and Gas carbon are exceptions.
  • Unlike metals, nonmetals aren’t malleable and ductile.
  • Nonmetals react more with metals than with nonmetals.
  • Usually, nonmetals react with other nonmetals at high temperatures.
  • Most nonmetals do not react with air at room temperature.
  • White phosphorus is the only nonmetal that reacts with air to form its oxide by burning.
  • Usually, nonmetals do not react with water. Except for Chlorine, chlorine dissolves in water to form an acidic solution.
  • Nonmetals have a low density.
  • They do not form alloys. However, nonmetals like carbon, silicon, and phosphorous.
  • Nonmetals exist in all states of matter at room temperature.
  • Different nonmetals have different reactions.
  • Chlorine is the most reactive metal in the halogen family i.e., Chlorine (Cl), Bromine (Br), Iodine (I), and Fluorine (F). The reactivity order of the halogen family is Cl > Br > I.
  • Therefore, Chlorine (Cl) can displace Bromine (Br) and Iodine (I) from solutions of bromides (NaBr) and Iodides (NaI).
  • Ionic solids are formed when nonmetals with high electronegativity react with alkali and alkaline earth metals.

Examples of Nonmetals

Examples of nonmetals include hydrogen, carbon, chlorine, helium, fluorine, nitrogen, phosphorus, and selenium.

Nonmetal Gas Elements

Most of the nonmetals are clear, odorless gases at room temperature. Hydrogen, helium, nitrogen, oxygen, neon, argon, krypton, xenon, and radon all fit into this category. 78% of our atmosphere is made up of nitrogen atoms, while 20% is made up of oxygen.

Chlorine is a yellow-green-colored gas with a distinct odor that burns the nostrils in high doses. You may have smelled it when visiting a chlorinated pool. Fluorine is a yellow gas that is equally unpleasant to smell and definitely more toxic. Radon is unstable and often radioactive. It seeps into underground basements and must be pumped out through ventilation systems.

Bromine is a brown liquid at room temperature that readily evaporates into a deep orange gas. It’s the only nonmetal element that exists in liquid form. Like chlorine and fluorine, bromine has a distinct odor and can be quite toxic.

Solid Nonmetal Elements

The remaining elements, carbon, phosphorus, sulfur, selenium, and iodine, exist in solid forms at room temperature. Each of these nonmetal elements has several different solid forms it can exist in, though some forms are more common than others.

For example, carbon is most commonly found as graphite, but it also forms diamonds. The most common form of sulfur is yellow and brittle solid and slightly stinky, like rotten eggs. Phosphorus has many forms, one of which is a gas, white phosphorus, that can ignite if exposed to oxygen. Iodine is often a brown solid that easily sublimes into purple vapors.

Noble Gases

Six nonmetals are classified as noble gases: helium, neon, argon, krypton, xenon, and radioactive radon. In conventional periodic tables, they occupy the rightmost column. They are called noble gases in light of their characteristically very low chemical reactivity.

They have very similar properties, all being colorless, odorless, and non-flammable. With their closed outer electron shells, the noble gases have feeble interatomic forces of attraction resulting in very low melting and boiling points. That is why they are all gases under standard conditions, even those with atomic masses larger than many normally solid elements.

Chemically, the noble gases have relatively high ionization energies, nil or negative electron affinities, and relatively high electronegativities. Compounds of the noble gases number in the hundreds although the list continues to grow, with most of these occurring via oxygen or fluorine combining with either krypton, xenon, or radon.

FAQs.

What are Nonmetals?

In chemistry, a nonmetal is a chemical element that generally lacks a predominance of metallic properties; they range from colorless gases to shiny and refractory (high melting point) solids. The electrons in nonmetals behave differently from those in metals.

What are the 10 non-metals?

The 17 nonmetal elements are hydrogen, helium, carbon, nitrogen, oxygen, fluorine, neon, phosphorus, sulfur, chlorine, argon, selenium, bromine, krypton, iodine, xenon, and radon.

How many nonmetals are there on the Periodic table?

There are 18 nonmetals on the Periodic table. All these nonmetals are located on the upper right corner of the Periodic table (Hydrogen is located in the left top corner). So, on considering Astatine as a nonmetal, there is a total of 18 nonmetals on the Periodic table. And if Astatine (At) is excluded from nonmetals, then there are a total of 17 nonmetals.

Why is this number inexact?

Because there is no widely agreed definition of metals, nonmetals, and semimetals. A chemist may define nonmetals on the basis of the chemical properties of the element, while a physicist may define nonmetals on the basis of density or atomic number. So, we can say that the total number of nonmetals on the Periodic table is 17 or 18.

What are examples of nonmetals?

Examples of nonmetals include hydrogen, carbon, chlorine, and helium. Properties of nonmetals include a relatively low boiling point, and poor conductivity; solid nonmetals are dull and brittle.

Where do you find nonmetals on the periodic table?

The metals are to the left of the line (except for hydrogen, which is a nonmetal), the nonmetals are to the right of the line, and the elements immediately adjacent to the line are the metalloids.

What group are the nonmetals in?

Group VIIA is the only group in the periodic table in which all the elements are nonmetals. This group contains F, Cl, Br, I, and At. The other name of this group is halogen which means salt producer.

What chemicals are similar to nonmetals?

Nonmetals share many similar properties including They are either gas (hydrogen, oxygen, nitrogen) or solid (carbon, sulfur) under standard conditions. They are not good conductors of electricity or heat. They are very brittle in their solid form.

What are nonmetals used for?

Liquid hydrogen is used as rocket fuel. Carbon in the form of graphite is used for making the electrodes of electrolytic cells and dry cells. Nitrogen is used in the manufacture of ammonia, nitric acid, and fertilizers. Nitrogen is used to preserve food materials.

What are the uses of nonmetals in our daily life?

For making electrical wires, cooking utensils, etc., copper is used. As a protective coating for iron, zinc is primarily used. Aluminum is used to produce electrical cables, packaging, utensils for cooking, etc. Non-metals Hydrogen is used in ammonia and methyl alcohol synthesis, welding torches, etc.

Who discovered nonmetals?

In 1789, French chemist Antoine Lavoisier tried grouping the elements as metals and nonmetals. Forty years later, German physicist Johann Wolfang Döbereiner observed similarities in the physical and chemical properties of certain elements.

What are the properties of nonmetal?

Physical Properties of Nonmetals, Non-Malleable and Ductile: Non-metals are very brittle, and cannot be rolled into wires or pounded into sheets. Conduction: They are poor conductors of heat and electricity. Luster: These have no metallic luster and do not reflect light.

What are some characteristics of non-metals?

In the elemental form, non-metals can be gas, liquid, or solid. They aren’t shiny (lustrous) and they don’t conduct heat or electricity well. Usually, their melting points are lower than for metals, although there are exceptions. The solids usually break easily, and can’t bend like metals.

What is the most likely reason that nonmetals are electrical insulators?

Since valence shells in nonmetal atoms are almost full, the atoms attract electrons and hold them tightly to fill their valence shells.

Are nonmetals dull?

Typical nonmetals have a dull, colored, or colorless appearance; are brittle when solid; are poor conductors of heat and electricity, and have acidic oxides.

How is oxygen a nonmetal?

The large values of the electronegativity and the electron affinity of oxygen are typical of elements that show only nonmetallic behavior. In all of its compounds, oxygen assumes a negative oxidation state as is expected from the two half-filled outer orbitals.

Are nonmetals good insulators?

Nonmetals do not allow either heat or electricity to flow through them easily. They are insulators. For example, heat does not pass easily through the air. Air is a mixture of several nonmetal gases, such as oxygen and nitrogen.

Are nonmetals semiconductors?

These elements called metalloids or sometimes semimetals, exhibit properties characteristic of both metals and nonmetals. The structures of these elements are similar in many ways to those of nonmetals, but the elements are electrical semiconductors.

Are nonmetals invisible?

They are not particularly malleable, and whereas most metals are shiny, nonmetals may be dull-colored, black (in the case of carbon in some forms or allotropes), or invisible, as is the case with most of the gaseous nonmetals.

What is the most reactive nonmetal?

The element fluorine is the most reactive nonmetal. It is not found in nature as a free element. Fluorine gas reacts explosively with many other elements and compounds and is considered to be one of the most dangerous known substances.