Non Metals - Definition, Examples, Properties, Uses, FAQs

Edited By Team Careers360 | Updated on Jul 02, 2025 05:06 PM IST

Metal and Non metal Definition: A non-metal is an element that forms negative ions by accepting or gaining electrons. In the outermost electron shell of non metals, there are usually 4, 5, 6 or 7 electrons. Electron conduction substances with finite activation energies (band gaps). The bulk electrical conductivity of nonmetal elements ranges from low (insulators) to moderate (semiconductors) and increases with increasing temperature. High voltages and temperatures can result in the dielectric breakdown of these materials. In addition to metals, nonmetal elements can also exist as solids, liquids, and gases. Nonmetal elements do not possess the same range of mechanical and optical properties as metals, such as brittleness and plasticity.

NEET 2025: Mock Test Series | Syllabus | High Scoring Topics | PYQs

JEE Main: Study Materials | High Scoring Topics | Preparation Guide

JEE Main: Syllabus | Sample Papers | Mock Tests | PYQs

Chemistry divides nonmetal elements into two categories:

1) covalent materials, which contain atoms with large size, high electronegativities, low valence vacancy ratios, and a tendency to form negative ions when reacted;

2) ionic materials, which contain crystals containing both small and large atoms. An ion can be created by adding electrons to (small, electronegative atoms) or by removing electrons from (large, electropositive atoms). The elements in the P and S blocks of the periodic table, as well as about 25% of the known elements from nonmetal elements at normal temperatures and pressures.

Graphite Crystalline

What is the meaning of non-metal?

Non metals are those types of materials that are devoid of all metallic properties. They are good heat and electricity insulators. Most of them are gases, but sometimes they're liquids. In some cases, they are even solid at normal room temperatures, such as is carbon a nonmetal, Sulphur, and phosphorous.

Also read -

Properties of Non metals

High electronegativity and high ionization energies are some of the properties of non metals. Since non metals have these properties, they usually gain electrons via covalent bonds when interacting with other compounds. The anionic dopants among the non metals exert a significant influence on the VB. Non-metallic dopants include carbon, nitrogen, fluorine, sulphur, and iodine.

These are the general properties of non metals.

The atoms in non metals are usually smaller than those in metals. In addition to their atomic size, non metals also have several other properties.
There is a very low electrical conductivity in non metals. Conductivity is the most important characteristic that distinguishes non metals from metals.
The electronegativities of nonmetal elements are high. Therefore, the atoms of non metals tend to attract more electrons than they typically would.
Non metals generally possess high electronegativities. Therefore, non-metallic atoms retain their electrons to maintain electrical continuity within the atom. Compared with non metals, metals are readily able to give up one or more electrons, thus forming positively charged ions freely, and metals readily conduct electricity.
Ordinary temperatures and pressures permit the generation of some non metals as gases, others as solids, one as a liquid.

NEET Highest Scoring Chapters & Topics

This ebook serves as a valuable study guide for NEET exams, specifically designed to assist students in light of recent changes and the removal of certain topics from the NEET exam.

Download EBook

In contrast with this, all metals are solid at room temperature except mercury. In normal atmospheric conditions, the melting and boiling points of non metals are relatively low because most of them exist as liquids or gases.

Related Topics Link - Metals and Nonmetals

Physical Properties of Nonmetal elements

Material to be stretched into wire which is ductile, but non metals are not ductile, except for carbon materials, used in a variety of applications including sports equipment and musical instruments.
As they do not have a shiny appearance, they are not lustrous.
The sound they make is not sonorous and does not sound as if they have a deep ring. In addition to this, they conduct heat and electricity poorly, except for graphite.

Example of Non metals with Room Temperature

Name of Non metal	State at room temperature
Hydrogen	Gas
Nitrogen	Gas
Oxygen	Gas
Fluorine	Gas
Chlorine	Gas
Iodine	Solid
Carbon	Solid

The above table shows nonmetal elements on periodic table

NCERT Chemistry Notes:

Chemical Properties of Non metals

A reaction between water and a chemical: There are few non metals that react with water, they are usually very reactive with air, that's why some of them are stored in water.
Chemical Reactions with Acids: There are no known reactions between non metals and acids.
Chemical Reactions with Bases: Non metals and bases interact in an extremely complex way. In reaction with bases like sodium hydroxide, chlorine creates products like sodium hypochlorite and sodium chloride.
A chemical reaction of non metals with oxygen: Reactions with oxygen resulting in the formation of oxides of non metals. Acidic or neutral properties are possessed by oxides of non metals. The result of the sulphur dioxide reaction is sulphur dioxide.

S+O₂→SO₂

When sulphur dioxide is combined with water, sulfuric acid is formed.

SO₂+H₂O→H₂SO₃

sulfur

Uses of Non-metals

Nitrogen is used to make ammonia, nitric acid, and fertilizers.
Chelating water is an important part of water purification.
As rocket fuel, hydrogen is very useful.
The graphite form of carbon can be used to make pencils.
Sulphur is used in the preparation of sulfuric acid.

Also check-

Frequently Asked Questions (FAQs)

1. What are some non metals examples?

Non-metallic elements include hydrogen, hydrogen, chlorine, fluorine, carbon, nitrogen, arsenic, phosphorus, selenium.

2. Is plastic non-metallic?

Metals and nonmetals are used to describe elements. The material known as plastic isn’t an element, but polymer composed of various non metals. Deformed plastics, however, are not all available.

3. What is the difference between metal and non-metal?

Metals can be solids, liquids, or gases. Non metals, except for graphite, have weak heat and electricity conducting abilities. There is no metallic lustre in our lives. Metal cannot make a ringing sound, nor do non metals. There are many nonmetal elements, such as carbon, oxygen, sulphur, phosphorus, etc.

4. What are Non-metallic materials?

The non-metallic elements of the periodic table are hydrogen, carbon, nitrogen, oxygen, as well as selenium etc.

5. What is meant by ductility?

An object's ductility refers to its ability so that they can withstand the tensile stress of any force which separates two ends of an object. Ductile refers to a metal that can be stretched into a thin wire without becoming weaker or more fragile.

6. How do non-metals differ from metals in their electron configuration?

Non-metals typically have 4-8 electrons in their outermost shell, while metals usually have 1-3 electrons. This difference leads to non-metals generally gaining electrons to achieve a stable electron configuration, whereas metals tend to lose electrons.

7. Why are most non-metals poor conductors of electricity?

Most non-metals are poor conductors of electricity because they don't have free electrons. Their electrons are tightly bound to their atoms in covalent bonds, unlike metals which have loosely held electrons that can move freely and conduct electricity.

8. Why are many non-metals gases at room temperature?

Many non-metals are gases at room temperature because they form small, light molecules with weak intermolecular forces. These weak forces allow the molecules to move freely as a gas at normal temperatures and pressures.

9. How do non-metals typically react with metals?

Non-metals typically react with metals to form ionic compounds. The metal loses electrons (oxidation) while the non-metal gains electrons (reduction). For example, sodium (metal) reacts with chlorine (non-metal) to form sodium chloride (table salt).

10. What is the "sea of electrons" model and why doesn't it apply to non-metals?

The "sea of electrons" model describes how valence electrons in metals are free to move throughout the material. This model doesn't apply to non-metals because their electrons are tightly bound in covalent bonds, not free to move around.

11. What role do non-metals play in biological systems?

Non-metals play crucial roles in biological systems. For example, carbon forms the backbone of all organic molecules, oxygen is essential for respiration, nitrogen is a key component of proteins, and phosphorus is vital for DNA and energy transfer (ATP).

12. What is the significance of non-metals in semiconductor technology?

Non-metals, particularly silicon and germanium, are crucial in semiconductor technology. Their unique electronic properties allow them to conduct electricity under certain conditions, making them ideal for use in electronic devices like transistors and solar cells.

13. How do non-metals contribute to the greenhouse effect?

Several non-metallic compounds, such as carbon dioxide (CO2), methane (CH4), and water vapor (H2O), are greenhouse gases. These molecules can absorb and emit infrared radiation, trapping heat in the Earth's atmosphere and contributing to global warming.

14. How do non-metals contribute to the formation of the ozone layer?

The ozone layer is primarily composed of the non-metal oxygen. Ozone (O3) is formed when ultraviolet radiation splits oxygen molecules (O2) into oxygen atoms, which then combine with other oxygen molecules to form ozone.

15. What is the relationship between non-metals and acid formation?

Many non-metals, particularly those in groups 15-17 of the periodic table, can form acids when combined with hydrogen. For example, chlorine forms hydrochloric acid (HCl), while sulfur forms sulfuric acid (H2SO4).

16. What are non-metals?

Non-metals are elements that generally lack metallic properties. They are typically poor conductors of heat and electricity, have low melting and boiling points, and are often brittle or gaseous at room temperature. Non-metals tend to gain electrons in chemical reactions and form covalent bonds.

17. Why are noble gases considered non-metals despite their low reactivity?

Noble gases are considered non-metals because they lack metallic properties like conductivity and malleability. Their low reactivity is due to their stable electron configurations, but they still exhibit non-metallic characteristics in terms of their physical properties.

18. What is the difference between a metalloid and a non-metal?

Metalloids are elements that exhibit properties of both metals and non-metals, while non-metals clearly lack metallic properties. Metalloids can conduct electricity under certain conditions, whereas most non-metals are poor conductors.

19. How do non-metals form bonds with other non-metals?

Non-metals typically form covalent bonds with other non-metals by sharing electrons. This sharing allows both atoms to achieve a stable electron configuration without completely transferring electrons as in ionic bonding.

20. How does the electronegativity of non-metals compare to that of metals?

Non-metals generally have higher electronegativity than metals. This means they have a stronger ability to attract electrons in a chemical bond, which is why they tend to gain electrons when reacting with metals.

21. How does the reactivity of non-metals change across a period in the periodic table?

The reactivity of non-metals generally increases from left to right across a period in the periodic table. This is because elements on the right have a higher electron affinity and are more likely to gain electrons to achieve a stable electron configuration.

22. Why are non-metals often brittle in their solid form?

Non-metals are often brittle in their solid form because they typically form covalent network structures or molecular solids. These structures don't allow for the easy movement or rearrangement of atoms that gives metals their malleability and ductility.

23. Why are some non-metals, like carbon, able to form long chains or networks?

Some non-metals, like carbon, can form long chains or networks due to their ability to form strong covalent bonds with themselves (a property called catenation). This allows them to create complex structures like diamonds or organic molecules.

24. How do the melting and boiling points of non-metals compare to those of metals?

Non-metals generally have lower melting and boiling points compared to metals. This is because the intermolecular forces between non-metal atoms or molecules are typically weaker than the metallic bonds in metals.

25. How do the atomic radii of non-metals change across a period in the periodic table?

The atomic radii of non-metals generally decrease from left to right across a period in the periodic table. This is because the increasing nuclear charge attracts the electrons more strongly, pulling them closer to the nucleus.

26. How do non-metals contribute to acid rain formation?

Non-metals like sulfur and nitrogen can form oxides (SO2 and NOx) that react with water in the atmosphere to produce acids. These acids then fall as acid rain, which can harm ecosystems and corrode structures.

27. Why are some non-metals, like phosphorus, stored under water?

Some non-metals, like white phosphorus, are highly reactive with oxygen in the air and can spontaneously ignite. Storing them under water prevents contact with air, reducing the risk of fire or oxidation.

28. How do the ionization energies of non-metals compare to those of metals?

Non-metals generally have higher ionization energies than metals. This means it takes more energy to remove an electron from a non-metal atom, which is why non-metals tend to gain rather than lose electrons in chemical reactions.

29. What is the importance of non-metals in the formation of organic compounds?

Non-metals, especially carbon, hydrogen, oxygen, and nitrogen, are the primary components of organic compounds. Their ability to form covalent bonds and create complex molecules is essential for life and forms the basis of organic chemistry.

30. How do non-metals contribute to the properties of polymers?

Non-metals like carbon, oxygen, and nitrogen are the main components of polymers. The covalent bonds between these non-metal atoms create long chains or networks, giving polymers their unique properties such as flexibility, strength, and resistance to heat or chemicals.

31. Why do some non-metals, like sulfur, have multiple allotropes?

Some non-metals have multiple allotropes (different structural forms of the same element) because they can form different arrangements of covalent bonds. For example, sulfur can exist as S8 rings or long chains, each with different properties.

32. How do non-metals interact with light compared to metals?

Non-metals generally interact with light differently than metals. While metals tend to reflect light, giving them their shiny appearance, non-metals may absorb, transmit, or scatter light depending on their structure and the wavelength of light.

33. What is the role of non-metals in the nitrogen cycle?

Non-metals play crucial roles in the nitrogen cycle. Nitrogen gas (N2) from the atmosphere is fixed into the soil by bacteria, converted to nitrates by other microorganisms, used by plants to make proteins, and then returned to the atmosphere through decomposition and denitrification.

34. How do non-metals contribute to the formation of chemical weapons?

Some non-metals and their compounds can be used in chemical weapons. For example, chlorine gas was used in World War I, and organophosphates (containing phosphorus) are used in nerve agents. It's important to note that such uses are prohibited by international law.

35. Why are some non-metals, like iodine, able to sublimate?

Some non-metals, like iodine, can sublimate (change directly from solid to gas) because the intermolecular forces between their molecules are weak enough that they can be overcome by room temperature, allowing the solid to transition directly to a gaseous state.

36. How do non-metals contribute to the formation of smog?

Non-metals play a significant role in smog formation. Nitrogen oxides and volatile organic compounds (containing carbon) react in the presence of sunlight to form ground-level ozone and other pollutants that constitute photochemical smog.

37. What is the importance of non-metals in water treatment processes?

Non-metals are crucial in water treatment. Chlorine is commonly used for disinfection, while carbon in activated charcoal filters can remove organic contaminants. Oxygen is also important in biological treatment processes.

38. How do non-metals contribute to the properties of ceramics?

Non-metals like oxygen, nitrogen, and carbon are essential components of many ceramics. They form strong covalent or ionic bonds with metals, creating materials that are typically hard, brittle, and resistant to high temperatures.

39. Why do some non-metals, like phosphorus, exhibit phosphorescence?

Phosphorescence in some non-metals, like phosphorus, occurs due to their electronic structure. When excited by light, electrons move to higher energy levels and then slowly return to their ground state, emitting light in the process.

40. How do non-metals contribute to the formation of vitamins?

Non-metals are essential components of vitamins. For example, vitamin C (ascorbic acid) is composed of carbon, hydrogen, and oxygen. Vitamin B12 contains cobalt, but also carbon, nitrogen, oxygen, and phosphorus.

41. What is the role of non-metals in the carbon cycle?

Non-metals, particularly carbon and oxygen, are central to the carbon cycle. Carbon dioxide in the atmosphere is used by plants in photosynthesis, incorporated into organic matter, consumed by animals, and returned to the atmosphere through respiration and decomposition.

42. How do non-metals contribute to the properties of explosives?

Many explosives are composed primarily of non-metals like carbon, hydrogen, nitrogen, and oxygen. These elements form unstable compounds that can rapidly decompose, releasing large amounts of energy and gas.

43. Why are some non-metals, like silicon, used in solar panels?

Some non-metals, like silicon, are used in solar panels due to their semiconductor properties. When light hits a silicon crystal, it can excite electrons, creating an electric current. This photovoltaic effect is the basis for solar energy conversion.

44. How do non-metals contribute to the formation of atmospheric halos and rainbows?

Non-metallic compounds in the atmosphere, particularly water droplets and ice crystals, are responsible for atmospheric phenomena like halos and rainbows. These occur due to the refraction, reflection, and dispersion of light by these non-metallic particles.

45. What is the importance of non-metals in the development of modern electronics?

Non-metals are crucial in modern electronics. Silicon and germanium are used as semiconductors in transistors and integrated circuits. Other non-metals like carbon (in carbon nanotubes) and phosphorus (in doping) also play important roles in electronic components.

46. How do non-metals contribute to the properties of superconductors?

While many superconductors contain metals, non-metals like oxygen, fluorine, and carbon also play crucial roles. For example, high-temperature superconductors often contain copper oxide layers, where the oxygen is essential to their superconducting properties.

47. Why are some non-metals, like helium, used in cryogenics?

Some non-metals, like helium, are used in cryogenics due to their extremely low boiling points. Liquid helium, with a boiling point of -268.9°C, is used to achieve very low temperatures necessary for certain scientific and medical applications.

48. How do non-metals contribute to the formation of aerosols?

Non-metals play a significant role in aerosol formation. Sulfur dioxide and nitrogen oxides can form small particles in the atmosphere. These, along with other non-metallic organic compounds, contribute to both natural (e.g., sea spray) and anthropogenic aerosols.

49. What is the role of non-metals in the formation of chemical sensors?

Non-metals are important in many chemical sensors. For example, carbon nanotubes can detect various gases by changes in their electrical properties. Oxygen sensors often use zirconia (containing the non-metal oxygen) to measure oxygen concentrations.

50. How do non-metals contribute to the properties of graphene?

Graphene, a single layer of carbon atoms, owes its remarkable properties to the non-metal carbon. The strong covalent bonds between carbon atoms in a hexagonal lattice give graphene its extraordinary strength, flexibility, and electrical conductivity.

51. Why are some non-metals, like argon, used in welding?

Some non-metals, like argon, are used in welding as shielding gases. Being inert, they protect the weld area from atmospheric gases that could react with the molten metal, ensuring a stronger, cleaner weld.

52. How do non-metals contribute to the properties of composite materials?

Non-metals play crucial roles in many composite materials. For example, carbon fibers (made of carbon atoms) provide strength and stiffness in carbon fiber reinforced polymers. The polymer matrix often contains non-metals like carbon, oxygen, and nitrogen.

53. What is the importance of non-metals in the development of fuel cells?

Non-metals are essential in fuel cell technology. Hydrogen and oxygen are the primary reactants in many fuel cells. Other non-metals like carbon (in electrodes) and fluorine (in membranes) are also crucial components in various types of fuel cells.

54. How do non-metals contribute to the properties of nanomaterials?

Non-metals are fundamental to many nanomaterials. Carbon forms various nanostructures like nanotubes and fullerenes. Silicon is used in quantum dots. The unique properties of these nanomaterials often arise from quantum effects due to their small size.

55. Why are some non-metals, like nitrogen, used in food packaging?

Some non-metals, like nitrogen, are used in food packaging to extend shelf life. Nitrogen is inert and can displace oxygen in packaging, which helps prevent oxidation and microbial growth, thus preserving food quality for longer periods.