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

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.

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.

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.

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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.

1. 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.
2. There is a very low electrical conductivity in non metals. Conductivity is the most important characteristic that distinguishes non metals from metals.
3. The electronegativities of nonmetal elements are high. Therefore, the atoms of non metals tend to attract more electrons than they typically would.
4. 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.
5. Ordinary temperatures and pressures permit the generation of some non metals as gases, others as solids, one as a liquid.

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.

Physical Properties of Nonmetal elements

1. 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.
2. As they do not have a shiny appearance, they are not lustrous.
3. 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

The above table shows nonmetal elements on periodic table

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Chemical Properties of Non metals

1. 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.
2. Chemical Reactions with Acids: There are no known reactions between non metals and acids.
3. 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.
4. 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

Uses of Non-metals

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

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