Non-metals are ...? Properties of nonmetals

Non-metals are elements that are significantly different in physical and chemical properties from metals. The reasons for their differences could be explained in detail only at the end of the 19th century, after the discovery of the electronic structure of the atom. What is the feature of nonmetals? What qualities are characteristic of the day? Let's figure it out.

Non-metals is what?

The approach to the separation of elements into metals and non-metals has long existed in the scientific community. The first in the periodic table of Mendeleyev is usually referred to as 94 elements. The non-metals of Mendeleev include 22 elements. In the periodic system, they occupy the upper right corner.

In a free form, nonmetals are simple substances, the main feature of which is the absence of characteristic metallic properties. They can be in all aggregate states. So, iodine, phosphorus, sulfur, carbon are found in the form of solids. The gaseous state is characteristic of oxygen, nitrogen, fluorine, etc. The liquid is only bromine.

In nature, the elements of nonmetals can exist both in the form of simple substances and in the form of compounds. In unbound form there are sulfur, nitrogen, oxygen. In compounds they form borates, phosphates, etc. In this form they are present in minerals, water, rocks.

The difference from metals

Non-metals are elements that differ from metals by appearance, structure and chemical properties. They have a large number of unpaired electrons at the external level, which means they are more active in oxidative reactions and more easily attach additional electrons to themselves.

The characteristic difference between the elements is observed in the structure of the crystal lattice. In metals, it is metallic. In non-metals it can be of two types: atomic and molecular. The atomic lattice gives substances a hardness and raises the melting point, it is inherent in silicon, boron, germanium. The molecular lattice is chlorine, sulfur, oxygen. It gives them volatility and little hardness.

The internal structure of the elements determines their physical properties. Metals have a characteristic luster, good conductivity of current and heat. They are hard, plastic, give in to forging, have a small color range (black, shades of gray, sometimes yellowish color).

Non-metals are liquid, gaseous or solid substances that do not have gloss and malleability. Their colors vary greatly and can be red, black, gray, yellow, etc. Almost all non-metals conduct poorly current (except carbon) and heat (except black phosphorus and carbon).

Chemical properties of nonmetals

In chemical reactions, non-metals can play the role of both oxidizing agents and reducing agents. When interacting with metals, they take on electrons, thus manifesting oxidizing properties.

Interacting with other non-metals, they behave differently. In such reactions, the less electronegative element manifests itself as a reducing agent, the more electronegative element acts as an oxidizer.

With oxygen, almost all (except fluorine) non-metals manifest themselves as reducing agents. When interacting with hydrogen, many are oxidizing agents, subsequently forming volatile compounds.

Part of the elements of nonmetals has the ability to form a few simple substances or modifications. This phenomenon is called allotropy. For example, carbon exists in the form of graphite, diamond, carbine and other modifications. They have two oxygen: ozone and oxygen proper. Phosphorus is red, black, white and metallic.

Non-metals in nature

In different quantities, non-metals are found everywhere. They are part of the earth's crust, are part of the atmosphere, hydrosphere, are present in the universe and in living organisms. In space, the most common are hydrogen and helium.

Within the Earth the situation is quite different. The most important components of the earth's crust are oxygen and silicon. They make up more than 75% of its mass. But the least amount is accounted for by iodine and bromine.

In the composition of sea water, oxygen accounts for 85.80%, and for hydrogen - 10.67%. Its composition also includes chlorine, sulfur, boron, bromine, carbon, fluorine and silicon. The composition of the atmosphere is dominated by nitrogen (78%) and oxygen (21%).

Non-metals, such as carbon, hydrogen, phosphorus, sulfur, oxygen and nitrogen, are important organic substances. They support the vital activity of all living beings on our planet, including people.