In 1869 D. I. Mendeleyev has formulated the fundamental law of the nature - the law of frequency. "Properties of simple bodies, also forms and properties of connections of elements, are in periodic dependence on the size of atomic vev of elements" On the basis of this law the Periodic Table has also been constructed. One of options of periodic system is given below.
s-elements
p-elements
d-elements
f-elements
Peri-
odes
ranks
I
II
III
IV
V
VI
VII
VIII
I
1
1 Hydrogen H
1,0079
2
Helium He
4,0026
II
2
3
Lithium Li
6,941
4
Beryllium Be
9,01218
5
Boron B
10,81
6
Carbon With
12,011
7
Nitrogen N
14,0067
8
Oxygen O
15,9994
9
Fluorine F
18,9984
10
Neon Ne
20,179
III
3
11
Sodium Na
22,98977
12
Magnesium Mg
24,305
13
Aluminum Al
26,98154
14
Silicon Si
28,0855
15
Phosphorus P
30,97376
16
Sulfur S
32,06
17
Chlorine Cl
35,453
18
Argon Ar
39,948
IV
4
19
Potassium K
39,0983
20
Calcium Ca
40,08
21
Scandium Sc
44,9559
22
Titanium Ti
47,88
23
Vanadium V
50,9415
24
Chrome Cr
51,996
25
Manganese Mn
54,9380
26
Iron Fe
55,847
27
Cobalt Co
58,9332
28
Nickel Ni
58,69
5
29
Copper Cu
63,546
30
Zinc Zn
65,38
31
Gallium Ga
69,72
32
Germanium Ge
72,59
33
Arsenic As
74,9216
34
Selenium Se
78,96
35
Bromine Br
79,904
36
Krypton Kr
83,80
V
6
37
Rubidium Rb
85,4678
38
Strontium Sr
87,62
39
Yttrium Y
88,9059
40
Zirconium Zr
91,22
41
Niobium Nb
92,9064
42
Molybdenum Mo
95,94
43
Technetium Tc
[98]
44
Ruthenium Ru
101,07
45
Rhodium Rh
102,9055
46
Palladium Pd
106,42
7
47
Silver Ag
107,868
48
Cadmium Cd
112,41
49
Indium In
114,82
50
Tin Sn
118,69
51
Antimony Sb
121,75
52
Tellurium Te
127,60
53
Iod I
126,9045
54
Xenon Xe
131,29
VI
8
55
Caesium Cs
132,9054
56
Barium Ba
137,33
57 *
Lanthanum La
138,9055
72
Hafnium Hf
178,49
73
Tantalum Ta
180,9479
74
Tungsten W
183,85
75
Rhenium Re
186,207
76
Osmium Os
190,2
77
Iridium Ir
192,22
78
Platinum Pt
195,08
9
79
Gold Au
196,9665
80
Mercury Hg
200,59
81
Thallium Tl
204,383
82
Lead Pb
207,2
83
Bismuth Bi
208,9804
84
Polonium Po
[209]
85
Astatine At
[210]
86
Radon Rn
[222]
VII
10
87
Francium Fr
[223]
88
Radium Ra
226,0254
89 **
Actinium Ac
227,0278
104
Rutherfordium Rf
[261]
105
Dubnium Db
[262]
106
Seaborgium Sg
[263]
107
Bohrium Bh
[262]
108
Hassium Hs
[265]
109
Maytnery Mt
[266]
110
Uun
[?]
*Lanthanides
58
Cerium Ce
140,12
59 Pra-
zeody Pr
140,9077
60
Neodymium Nd
144,24
61 Missile defense -
softenings Pm
[145]
62
Samarium Sm
150,36
63
Europium Eu
151,96
64 Gado-
lines Gd
157,25
65
Terbium Tb
158,9254
66 Dis-
proziya Dy
162,50
67
Gol-
miya Ho
164,9304
68
Erbium Er
167,26
69
Thulium Tm
168,9342
70
Ytterbium Yb
173,04
71
Lutetium Lu
174.967
**Actinoids
90
Thorium Th
232,0381
91 Prot-
actinium Pa
231,0359
92
Uranium U
238,0389
93 Nep-
tuniya Np
237,0482
94
Plutonium Pu
[244]
95
Americium Am
[243]
96
Curium Cm
[247]
97
Berkelium Bk
[247]
98 Kali -
forniya Cf
[251]
99 Eyn-
shteyniya Es
[252]
100
Fermium Fm
[257]
101 Mende -
levi Md
[258]
102 But -
is more white No
[255]
103 Lowe -
rensiya Lr
[260]
The table is divided into the periods, ranks, groups. Certain place in it is provided to each chemical element. Each chemical element has order number, atomic mass, the name, chemical symbol.
Let's take the first chemical element hydrogen. The Order number-1, atomic mass-1,0079, chemical symbol - N.
Each of components of periodic system, makes certain physical sense, исполузуя the table we can define some characteristics of atom of element. 1. Order number. We can determine nuclear charge of atom, number of electrons in atom by it and number of protons in kernel. As practically all mass of atom is concentrated in kernel, we can find number of neutrons, having subtracted order number from atomic mass. Example: let's take chemical element gold. The number of protons is equal 79, neutrons - (197-79=118). We round atomic mass to entire quantity, using rules of rounding which are known to you from mathematics course. 2. To number of the period there corresponds the number of energy levels on which electrons are located. 3. We can determine the highest valency of chemical element by number of group. Groups are divided into two subgroups: main and collateral. The main subgroup is formed also by p-elements. For the main subgroup to number of group there corresponds the number of electrons on external energy level. In the main subgroups both metals, and nonmetals are located.
d-and f-elements form secondary subgroup.
How properties of simple substances, depending on situation in periodic system change?
In the periods there is weakening of metallicity, strengthening from left to right - nonmetallic. In groups metallicity from top to down amplify, nemetellichesky are weakened. Patterns and for connections are observed. About it it will be told when studying classes of non-organic substances.
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