Definition: What are nonmetals?

Nonmetals are those elements in the periodic table that do not have the typical characteristics of metals such as electrical conductivity, hardness, and ductility ^[1].

Where are nonmetals located in the periodic table?

The nonmetals are located on the right-hand side of the periodic table (except hydrogen, which is the first element and located on the left). They are positioned to the right of the metalloids. Most of the p-block elements are nonmetals. The two artificial elements Tennessine and Oganesson are generally considered as nonmetal, although more studies are required ^[2].

List of nonmetals There are 20 nonmetals in the periodic table that including the halogen and the noble gases [3].
Family	Element	Symbol	Atomic Number
Regular nonmetal	Hydrogen	H	1
	Carbon	C	6
	Nitrogen	N	7
	Oxygen	O	8
	Phosphorus	P	15
	Sulfur	S	16
	Selenium	Se	34
Halogen	Fluorine	F	9
	Chlorine	Cl	17
	Bromine	Br	35
	Iodine	I	53
	Astatine	At	85
	Tennessine	Ts	117
Noble gas	Helium	He	2
	Neon	Ne	10
	Argon	Ar	18
	Krypton	Kr	36
	Xenon	Xe	54
	Radon	Rn	86
	Oganesson	Og	118

Common Properties and Characteristics of Nonmetals

Nonmetals display a wider range of properties than metals, especially their chemical properties and reactivity. The properties of nonmetals depend on their molecular structure and the strength of the interatomic bonding. Diamond and graphite are allotropic forms of carbon and have some properties different from other nonmetals.

Physical Properties of Nonmetals ^{[4, 5]}

• Exist in all three states of matter in the monoatomic or diatomic form (except Ozone O₃)
• Have high ionization energy
• Poor conductor of heat and electricity (except graphite)
• Brittle and not malleable or ductile (except diamond)
• Show no luster – dull and non-shiny (except diamond)
• Lower melting and boiling points than metals
• Lighter substances with lower density than metals
• Do not reflect any light (except diamond)
• Non-sonorous, i.e., do not produce sound when struck

Chemical Properties of Nonmetals ^{[4, 5, 6, 7, 8, 9]}

• Highly electronegative that form compounds by accepting electrons from other atoms
• Does not react with water (except chlorine) and acid
• Form complex reactions with bases to give salts
  • For example, Cl reacts with NaOH to give NaClO, NaCl, and H₂
• Form ionic or covalent compounds with metals (e.g., NaCl and KBr)
• Very reactive in air, especially at high temperatures (e. g., phosphorous catches fire when exposed to air)
• Reacts with oxygen to give oxides (e.g., SO₂, SO₃, P₃O₅, and P₄O₆)
• Form stable compounds with hydrogen (e.g., H₂S and Na₂HPO₄)

Uses and Application of Nonmetals ^{[10, 11, 12]}

Nonmetals have a variety of uses in daily life. Besides, the allotropic forms of carbon like graphite, diamond, charcoal, and coke have their unique applications.

• Carbon is found primarily in every object that we see (e.g., paper, plastic, and wood).
• Carbon black is used for making rubber tires.
• Graphite, being a good conductor of electricity, is used in electronic devices and as for lubrication.
• Diamond is used for making jewelry and in glass cutting.
• Charcoal is used as fuel in old train engines and also in water purifiers for filtration.
• Hydrogen is used in electric batteries for battery-operated vehicles and as rocket fuel.
• Helium, being light, is used in balloons.
• Neon, argon, and krypton are used in different kinds of lights.
• Nitrogen is used to manufacture explosives and ammonia, which is an essential ingredient in fertilizers.
• Oxygen is used for respiration and stored in an oxygen cylinder.
• Ozone protects us from the harmful ultraviolet rays of the sun.
• Chlorine is used as a bleaching agent to remove stains, in plastics like PVC for water pipes, and for purifying water by killing bacteria.
• Bromine is used in the manufacture of flame-retardant materials and as a disinfectant.
• Iodine is used as an antiseptic in wounds and cuts.
• Phosphorous is used in fertilizers that help in plant growth and in flares (white phosphorous).
• Phosphorous and sulfur are used in firecrackers and in matchboxes (white phosphorous).
• Sulfur is used in the vulcanization of rubber, in gunpowder, and as sulfuric acid in batteries.
• Selenium is used in anti-dandruff shampoo (selenium sulfide).

FAQs

Q.1. Which are the four most abundant nonmetals in nature?

Ans. The four most abundant nonmetals are hydrogen, oxygen, carbon, and nitrogen.

Q.2. Why do most nonmetals cannot conduct electricity?

Ans. Unlike metals, most nonmetals do not give away electrons and hence, prevent the flow of electricity.

Q.3. Is hydrogen a metal or nonmetal?

Ans. Hydrogen is a nonmetal but tends to form H⁺ ion like an alkali metal. Recent discoveries by Harvard researchers have shown that upon application of high-pressure hydrogen can be converted into a metallic form.

Q.4. What is the most reactive nonmetal?

Ans. Fluorine is the most reactive nonmetal since it has a valency of 1 and has a tendency to attract an electron to complete its outer shell.

Q.5. Which property do metalloids share with nonmetals?

Ans.

1. Both have low elasticity and are brittle.
2. Both tend to gain electrons during chemical reactions.
3. Metalloids react with metals to form alloys. Nonmetals react with metals to form compounds.
4. Some metalloids are dull in appearance, like nonmetals.

References
1. Definition – Byjus.com
2. Location  – Vedantu.com
3. List – Thoughtco.com
4. Physical Properties – Thoughtco.com
5. General Properties  – Funscience.in
6. General Properties  – Bitannica.com
7. Chemical Properties – Byjus.com
8. Chemical Properties – Jagranjosh.com
9. Chemical Properties – Toppr.com
10. Uses and Applications – Byjus.com
11. Uses and Applications – Vedantu.com
12. Uses and Applications – Schooledbyscience.com