All currently known chemical elements have a common "house" - a periodic system. However, they are located there not as necessary, but in a strict order, of a certain sequence. One of the main criteria by which all atoms are classified are characteristics.
The physical properties of non-metals and representatives of metal elements are the basis on which not only their separation within the table is based, but also the scope of human use. Let's get to know closer with non-metals and their characteristics.
Position in the periodic system
If we consider the system of chemical elements as a whole, then we can determine the position of non-metals as follows:
- Upper right corner.
- Above the conditional boundary diagonal from boron to astatine.
- The main subgroups are from group IV-VIII.
Obviously, their number is clearly inferior to that of metals. In terms of numbers, this will be approximately 25/85. However, this fact in no way reduces their significance and importance. Moreover, the physical properties of non-metals are much more diverse than those of their "opponents."
Varieties of simple non-metal compounds
Several main categories are identified, to which all known elements are considered. The physical properties of simple substances - non-metals - allow us to divide them into:
Moreover, there is a special group of elements - noble gases. According to their characteristics, they do not belong to any of the designated categories.
Gaseous non-metals
There are a lot of those. These include such simple substances as:
- oxygen;
- nitrogen;
- halogens chlorine and fluorine;
- hydrogen;
- white phosphorus;
- ozone.
However, this is possible subject to standard environmental parameters. The crystal lattice of these representatives is molecular, the type of chemical bond in the molecules is non-polar covalent. The physical properties of non-metals of this group are similar. They possess:
- compressibility;
- the ability of unlimited mixing among themselves;
- extensibility;
- fill the entire volume of the vessel.
Among the listed substances, two are poisonous - chlorine and white phosphorus. Very dangerous, asphyxiating compounds. At the same time, chlorine is a yellow-green gas, phosphorus is white, highly flammable in air.
Oxygen and ozone are good oxidizing agents. The first is the constant component of air necessary for the life of most organisms. The second is formed after a thunderstorm due to the action of lightning electrical discharges on atmospheric oxygen. Has a pleasant smell of freshness.
Liquid non-metals
The physical properties of non-metals of this group can be described by characterizing only one substance - bromine. Since only it is a liquid under ordinary conditions among all representatives of the considered group of elements.
This is a dark brown liquid, heavy enough, which is the strongest poison. Even bromine vapors can cause complex ulcers on the hands that do not heal for a long time. Its smell is very unpleasant, for which the element got its name (translated bromos - fetid).
By its chemical characteristics, bromine is an oxidizing agent for metals and a reducing agent for stronger non-metals than it is.
Despite these features, bromine ions must be present in the human body. Without it, diseases associated with hormonal disorders occur.
Solid representatives
Simple substances of this category include most non-metals. It:
- boron;
- all allotropic modifications of carbon;
- red and black phosphorus;
- sulfur;
- silicon;
- arsenic;
- one of the tin modifications.
All of them have an atomic crystal lattice, rather solid, but brittle substances. Black phosphorus is a dry, greasy to the touch compound. Red is a pasty mass.
The hardest of all these substances is diamond - a kind of carbon. The physical and chemical properties of non-metals of this group are very different, since some of them are far from each other in the table. This means that the oxidation state, the shown chemical activity, the nature of the compounds - all these indicators will vary.
An interesting non-metal in the solid state is iodine. Its crystals shine on the cut, thereby showing similarity with metals. This is not surprising, because it is located almost on the border with them. This substance also has a special property - sublimation. When heated, iodine passes into a gaseous state, bypassing the liquid. Its pairs have a bright purple saturated color.
Physical properties of non-metals: table
In order to more easily indicate what non-metals are, it is better to build a generalizing table. It will show what are the general physical properties of non-metals, and what are their differences.
| Physical property | Nonmetal example |
| Physical state under normal conditions | All three are characteristic: solid (sulfur, carbon, silicon and others), gaseous (for example, halogens), liquid (bromine) |
| Electrical and thermal conductivity | Not characteristic of anything but carbon and black phosphorus |
| Simple substance coloring | Very diverse. Example: bromine is red, sulfur is yellow, iodine crystals are dark violet, carbon in the form of graphite is dark gray, chlorine is yellow-green and so on. |
| Metallic luster | It is characteristic only for crystalline iodine |
| Durability and ductility | Completely absent. All solids are brittle, except diamond and some forms of silicon |
Obviously, differences in physical properties of non-metals are more prevalent than similarities. If for metals it is possible to distinguish several characteristics under which each of them will fall, then for the elements considered by us this is impossible.