Atoms of most metals have in external orbit, or, as they say, at the external energy level, a relatively small number of electrons (one, two, three). The most stable external electronic shells, as you know, have inert gases: Helia has two electrons, all other gases have eight gas. During chemical reactions, the atoms of all elements “strive” to get just such an external shell. This can be done in two ways: having given all the electrons of its outer orbit and exposing the one that lies under it, or having completed the outer orbit of up to eight electrons. Naturally, it is easier to give metals in the outer layer a small number of electrons, and to purchase non -metals, which have four or more electrons, respectively, to purchase. However, tin and lead have four electrons in the outer layer, antimony and bismuth – five, and polonium even six electrons, and yet it is more likely metals than non -metals. Why?
From a chemical point of view, a single atom is all the more metal, the easier it gives the electrons of its outer layer. And it depends not only on their number here, but also on the size of the atom itself: the larger it is, the less power it holds the core of the electrons of its distant external orbit. The energy that needs to be spent on the separation from the atom of one electron from the outer layer is called the potential of ionization. It is least of France, which has only one electron in the most distant orbit from the nucleus. That is why France is the most metallic of all the elements known so far. Of course, this is a rare metal and is extremely rare in industry, but other more common metals are used more often and they are traded by the London non -ferrous metals exchange.
The largest ionization potential (not counting inert gases) in fluorine – the most non -metallic of all elements. So it should be: he has a small atom – only two electronic levels, and in the orbit close to the nucleus, as many as seven electrons. There is not enough only one to the “magnificent eight”, and the fluorine fiercely takes the missing electron in almost any element.
Due to the large removal of the electronic shell from the nucleus, the value of the ionization potential in tin, lead, antimony, bismuth and even polonium are relatively small, and they have many metallic properties, despite the large number of electrons in external orbit.
Looking at the periodic table, it is easy to find out the structure of the atom of any element. The serial number of each element in the table is numerically equal to the positive charge of the nucleus. The period of the period shows how many electronic layers are around the nucleus, the number of the group is the number of valence electrons. Each cage of the table indicates the number of electrons at all energy levels. Take a look at these columns more closely. The lowest shows the number of electrons in the layer closest to the nucleus, and the highest – in the external.
According to the laws of quantum mechanics at each energy level, there may be no more than a specific number of electrons: in the nearest to the core – two, in the next – eight, then 18.32 and t respectively, respectively. D. The maximum possible number of electrons in any layer is 2P-KV, where P is the layer number. In this case, the electronic shell of each subsequent element completely includes the electronic shells of the previous element in the table.
Let’s trace how the electronic shells are built up in different elements. In the second and third periods of the periodic table, the development is only in the outer membranes. Until the construction of the lower shell ends, the upper one does not begin to be built. Each new electron in the shell sharply changes the properties of the element. As a result, oxygen is not at all like nitrogen, chlorine – sulfur. With each new electron in the outer shell, the non -metallic properties of the element are enhanced, but the price of metal is primarily formed by the demand for this metal in industry and the metallurgical market and, first of all, the cost determines the London exchange price for the metal of which is taken into account by the whole world.