- Mendeleev Table
Table Mendeleev as in high-rise apartment building "live" chemical elements, eachwhich occupies his own apartment.Thus, each of the elements has a certain sequence number indicated in the table.Numbering begins chemical elements from left to right and top.Table horizontal rows called periods and the vertical columns - groups.This is important because the number of groups or period may also be given some parameters characteristic atom .
atom is chemically indivisible particles, but it is composed of smaller
components, which include protons (positively charged particles), electrons (negatively charged) and neutrons (neutral particles).The bulk atom is concentrated in the nucleus (due to protons and neutrons) around which electrons revolve.In general, the atom is electrically neutral, that is it the number of positive charges same as the number of negative, hence the number of protons and electrons equally.The positive charge of the nucleus atom takes place just due to protons.
is necessary to remember that the serial number of the chemical element quantitatively coincides with the nucleus charge atom .Therefore, to determine the charge of the nucleus atom need to see what number is this chemical element.
Example № 1. Determine the charge core carbon atoms (C).We start to analyze the chemical element carbon, focusing on the Mendeleev table.Carbon is stored in the "apartment» № 6. Consequently, it has a core charge +6 by 6 protons (positively charged particles), which are located in the nucleus.Given that the atom is electrically neutral, then the electrons will also 6.
Example № 2. Identify the core charge atom of aluminum (Al).Aluminum has a serial number - № 13. Therefore, the charge nucleus of an atom of aluminum 13 (from the 13 protons).Electrons also 13.
Example № 3. Identify core charge atom of silver (Ag).Silver has a serial number - № 47. Therefore, the charge of the nucleus atom Silver + 47 (by 47 protons).Electrons also 47.
table Mendeleev in one cell for each chemical element listed two numeric values.Do not confuse the serial number and the relative atomic mass of the element