Pulse collision tel. Savelyev I.V.
The degree of oxidation is the conditional charge of the atoms of the chemical element in the compound calculated from the assumption that all links have an ion type. The degrees of oxidation may have a positive, negative or zero value, therefore the algebraic amount of the degrees of the oxidation of elements in the molecule, taking into account the number of their atoms, is 0, and in the ion - ion charge.
This list of oxidation degrees shows all the well-known degrees of oxidation of the chemical elements of the periodic table of Mendeleev. The list is based on the Greenwood Table with all additions. In lines that are highlighted by color, the inert gases are ins. The degree of oxidation of which is zero.
| 1 | −1 | H. | +1 | ||||||||||
| 2 | He. | ||||||||||||
| 3 | LI | +1 | |||||||||||
| 4 | -3 | BE. | +1 | +2 | |||||||||
| 5 | −1 | B. | +1 | +2 | +3 | ||||||||
| 6 | −4 | −3 | −2 | −1 | C. | +1 | +2 | +3 | +4 | ||||
| 7 | −3 | −2 | −1 | N. | +1 | +2 | +3 | +4 | +5 | ||||
| 8 | −2 | −1 | O. | +1 | +2 | ||||||||
| 9 | −1 | F. | +1 | ||||||||||
| 10 | Ne | ||||||||||||
| 11 | −1 | Na. | +1 | ||||||||||
| 12 | MG. | +1 | +2 | ||||||||||
| 13 | Al | +3 | |||||||||||
| 14 | −4 | −3 | −2 | −1 | SI | +1 | +2 | +3 | +4 | ||||
| 15 | −3 | −2 | −1 | P. | +1 | +2 | +3 | +4 | +5 | ||||
| 16 | −2 | −1 | S. | +1 | +2 | +3 | +4 | +5 | +6 | ||||
| 17 | −1 | Cl. | +1 | +2 | +3 | +4 | +5 | +6 | +7 | ||||
| 18 | AR | ||||||||||||
| 19 | K. | +1 | |||||||||||
| 20 | CA. | +2 | |||||||||||
| 21 | SC | +1 | +2 | +3 | |||||||||
| 22 | −1 | TI | +2 | +3 | +4 | ||||||||
| 23 | −1 | V. | +1 | +2 | +3 | +4 | +5 | ||||||
| 24 | −2 | −1 | CR | +1 | +2 | +3 | +4 | +5 | +6 | ||||
| 25 | −3 | −2 | −1 | MN. | +1 | +2 | +3 | +4 | +5 | +6 | +7 | ||
| 26 | −2 | −1 | FE. | +1 | +2 | +3 | +4 | +5 | +6 | ||||
| 27 | −1 | Co. | +1 | +2 | +3 | +4 | +5 | ||||||
| 28 | −1 | Ni. | +1 | +2 | +3 | +4 | |||||||
| 29 | Cu. | +1 | +2 | +3 | +4 | ||||||||
| 30 | Zn. | +2 | |||||||||||
| 31 | GA. | +1 | +2 | +3 | |||||||||
| 32 | −4 | GE. | +1 | +2 | +3 | +4 | |||||||
| 33 | −3 | As | +2 | +3 | +5 | ||||||||
| 34 | −2 | SE | +2 | +4 | +6 | ||||||||
| 35 | −1 | Br. | +1 | +3 | +4 | +5 | +7 | ||||||
| 36 | Kr. | +2 | |||||||||||
| 37 | RB. | +1 | |||||||||||
| 38 | Sr. | +2 | |||||||||||
| 39 | Y. | +1 | +2 | +3 | |||||||||
| 40 | Zr. | +1 | +2 | +3 | +4 | ||||||||
| 41 | −1 | NB. | +2 | +3 | +4 | +5 | |||||||
| 42 | −2 | −1 | Mo. | +1 | +2 | +3 | +4 | +5 | +6 | ||||
| 43 | −3 | −1 | TC. | +1 | +2 | +3 | +4 | +5 | +6 | +7 | |||
| 44 | −2 | Ru | +1 | +2 | +3 | +4 | +5 | +6 | +7 | +8 | |||
| 45 | −1 | Rh. | +1 | +2 | +3 | +4 | +5 | +6 | |||||
| 46 | Pd. | +2 | +4 | ||||||||||
| 47 | AG | +1 | +2 | +3 | |||||||||
| 48 | CD | +2 | |||||||||||
| 49 | IN. | +1 | +2 | +3 | |||||||||
| 50 | −4 | SN. | +2 | +4 | |||||||||
| 51 | −3 | SB. | +3 | +5 | |||||||||
| 52 | −2 | TE. | +2 | +4 | +5 | +6 | |||||||
| 53 | −1 | I. | +1 | +3 | +5 | +7 | |||||||
| 54 | Xe. | +2 | +4 | +6 | +8 | ||||||||
| 55 | CS. | +1 | |||||||||||
| 56 | BA. | +2 | |||||||||||
| 57 | LA | +2 | +3 | ||||||||||
| 58 | CE | +2 | +3 | +4 | |||||||||
| 59 | Pr. | +2 | +3 | +4 | |||||||||
| 60 | ND. | +2 | +3 | ||||||||||
| 61 | PM. | +3 | |||||||||||
| 62 | SM. | +2 | +3 | ||||||||||
| 63 | EU | +2 | +3 | ||||||||||
| 64 | GD. | +1 | +2 | +3 | |||||||||
| 65 | TB. | +1 | +3 | +4 | |||||||||
| 66 | DY. | +2 | +3 | ||||||||||
| 67 | HO. | +3 | |||||||||||
| 68 | ER. | +3 | |||||||||||
| 69 | TM. | +2 | +3 | ||||||||||
| 70 | YB. | +2 | +3 | ||||||||||
| 71 | Lu. | +3 | |||||||||||
| 72 | HF. | +2 | +3 | +4 | |||||||||
| 73 | −1 | TA. | +2 | +3 | +4 | +5 | |||||||
| 74 | −2 | −1 | W. | +1 | +2 | +3 | +4 | +5 | +6 | ||||
| 75 | −3 | −1 | Re. | +1 | +2 | +3 | +4 | +5 | +6 | +7 | |||
| 76 | −2 | −1 | OS | +1 | +2 | +3 | +4 | +5 | +6 | +7 | +8 | ||
| 77 | −3 | −1 | IR. | +1 | +2 | +3 | +4 | +5 | +6 | ||||
| 78 | Pt. | +2 | +4 | +5 | +6 | ||||||||
| 79 | −1 | AU. | +1 | +2 | +3 | +5 | |||||||
| 80 | Hg. | +1 | +2 | +4 | |||||||||
| 81 | TL | +1 | +3 | ||||||||||
| 82 | −4 | PB. | +2 | +4 | |||||||||
| 83 | −3 | BI | +3 | +5 | |||||||||
| 84 | −2 | PO | +2 | +4 | +6 | ||||||||
| 85 | −1 | AT. | +1 | +3 | +5 | ||||||||
| 86 | RN. | +2 | +4 | +6 | |||||||||
| 87 | Fr. | +1 | |||||||||||
| 88 | RA | +2 | |||||||||||
| 89 | AC | +3 | |||||||||||
| 90 | TH. | +2 | +3 | +4 | |||||||||
| 91 | PA | +3 | +4 | +5 | |||||||||
| 92 | U. | +3 | +4 | +5 | +6 | ||||||||
| 93 | NP. | +3 | +4 | +5 | +6 | +7 | |||||||
| 94 | Pu | +3 | +4 | +5 | +6 | +7 | |||||||
| 95 | AM. | +2 | +3 | +4 | +5 | +6 | |||||||
| 96 | Cm. | +3 | +4 | ||||||||||
| 97 | Bk. | +3 | +4 | ||||||||||
| 98 | CF. | +2 | +3 | +4 | |||||||||
| 99 | Es | +2 | +3 | ||||||||||
| 100 | FM. | +2 | +3 | ||||||||||
| 101 | MD. | +2 | +3 | ||||||||||
| 102 | No. | +2 | +3 | ||||||||||
| 103 | LR | +3 | |||||||||||
| 104 | Rf | +4 | |||||||||||
| 105 | DB | +5 | |||||||||||
| 106 | SG. | +6 | |||||||||||
| 107 | Bh. | +7 | |||||||||||
| 108 | HS. | +8 |
The highest degree of oxidation of the element corresponds to the number of the periodic system number, where this element is located (the exclusion is: AU + 3 (I group), Cu + 2 (II), from the VIII group the degree of oxidation +8 can only be among OS os and ruthenium RU.
The degree of oxidation of metals in connections
The degrees of oxidation of metals in the compounds are always positive, but to talk about nonmetallah, their degree of oxidation depends on which it is connected to the atom:
- if with a nonmetal atom, the degree of oxidation can be positive and negative. It depends on the electronegativity of the atoms of the elements;
- if with a metal atom, then the degree of oxidation is negative.
Negative degree of oxidation of non-metals
The highest negative degree of oxidation of non-metals can be determined by subtraction from the 8th group number in which this chemical element. The highest positive degree of oxidation is equal to the number of electrons on the outer layer, which corresponds to the number number.
Please note that the degrees of oxidation of simple substances are equal to 0, regardless of whether it is metal or nonmetall.
Sources:
- Greenwood, Norman N.; Earnshaw, A. Chemistry of the Elements - 2nd ed. - Oxford: Butterworth-Heinemann, 1997
- Green Stable Magnesium (i) Compounds with MG-MG Bonds / Jones C.; Stasch A .. - Journal Science, 2007. - December (Vol. 318 (No. 5857)
- Science magazine, 1970. - Vol. 3929. - № 168. - P. 362.
- Journal of the Chemical Society, Chemical Communications, 1975. - S. 760B-761.
- Irving Langmuir The Arrangement of Electrons in Atoms and Molecules. - J. AM magazine. Chem. SOC., 1919. - Vol. 41.
Modern wording Periodic Law, Open D. I. Mendeleev in 1869:
Properties of elements are in periodic dependence on the sequence number.
The periodically repeated nature of the change in the composition of the electronic shell of the atoms of the elements explains the periodic change in the properties of elements when driving around periods and groups Periodic system.
For example, a change in the highest and lower degrees of oxidation in elements Ia - VIIA groups in the second - fourth periods in the table. 3.
Positive The degree of oxidation exhibit all the elements, with the exception of fluoride. Their values \u200b\u200bincrease with the growth of the chores and coincide with the number of electrons at the last energy level (with the exception of oxygen). These oxidation degrees are called high Degrees of oxidation. For example, the highest degree of oxidation of phosphorus p is equal to + v.
Negative The degrees of oxidation exhibit elements, starting with carbon C, silicon Si and Germany GE. The values \u200b\u200bof them are equal to the number of electrons missing up to eight. These oxidation degrees are called lower Degrees of oxidation. For example, a phosphorus atom in the last energy level lacks three electrons to eight, it means that the lowest degree of oxidation of phosphorus P is equal to - III.
The values \u200b\u200bof the highest and lower degrees of oxidation are repeated periodically, coinciding in groups; For example, in IVA-group, carbon C, silicon Si and germanium GE have the highest oxidation of + iv, and the lower degree of oxidation is IV.
This frequency of change of oxidation degrees is reflected in the periodic change in the composition and properties chemical compounds Elements.
Similarly, a periodic change in the electronegability of elements in the 1-6th period of IA-VIIA groups (Table 4) is traced.
In each period of the periodic system, the electronegability of the elements increases with an increase in the sequence number (from left to right).
In each group Periodic system Electricity decreases with an increase in the sequence number (from top to bottom). Fluoro F has the highest, and Cesium CS is the lowest electronegitability among the elements of the 1-6 periods.
Typical non-metals - high electrothricate, and typical metals - low.
Examples of assignments of parts A, in1. In the 4th period, the number of elements is equal
2. Metal properties of the elements of the 3rd period from Na to CL
1) Silence
2) Weaken
3) do not change
4) I do not know
3. Non-metallic properties of halogens with an increase in the sequence number
1) increase
2) Fresh
3) remain unchanged
4) I do not know
4. In a number of Zn elements - HG - CO - CD one element that is not included in the group is
5. Metal properties of elements rise in a row
1) in - Ga - Al
2) K - RB - SR
3) GE - GA - TL
4) Li - BE - MG
6. Non-metallic properties in a row of elements AL - SI - C - N
1) increase
2) decrease
3) do not change
4) I do not know
7. In a number of elements O - S - SE - those dimensions (radii) atom
1) decrease
2) increase
3) do not change
4) I do not know
8. In a number of elements P - SI - AL - MG dimensions (radii) atom
1) decrease
2) increase
3) do not change
4) I do not know
9. For phosphorus element with Lesser Electricity is
10. Molecule in which electronic density is shifted to the phosphorus atom - this
11. Higher The degree of oxidation of the elements is manifested in the set of oxides and fluorides
1) CLO 2, RSL 5, SECL 4, SO 3
2) PCL, AL 2 O 3, KSL, with
3) SEO 3, HVL 3, N 2 O 5, SASL 2
4) ASCL 5, SEO 2, SCL 2, CL 2 O 7
12. Lowest The degree of oxidation of elements - in their hydrogen compounds and dial fluorides
1) CLF 3, NH 3, NAH, of 2
2) H 3 S +, NH +, Sih 4, H 2 SE
3) CH 4, BF 4, H 3 O +, PF 3
4) PH 3, NF +, HF 2, CF 4
13. Valence for a multifaceted atom The same in a number of connections
1) SIH 4 - ASH 3 - CF 4
2) pH 3 - BF 3 - CLF 3
3) ASF 3 - SICL 4 - IF 7
4) H 2 O - BCLG - NF 3
14. Specify the correspondence between the formula of substance or ion and the degree of carbon oxidation in them
Question number 5. "The highest degree of nitrogen oxidation in compounds is greater than the highest degree of carbon oxidation, since ..."
At the external energy level of the nitrogen atom there are 5 electrons, the electronic formula of the outer layer of the nitrogen atom, the highest degree of oxidation is +5.
At the external energy level of the carbon atom in an excited state there are 4 paired electrons, the electronic formula of the outer layer of carbon atom, the highest degree of oxidation is +4.
Answer: on the outer electron layer of the nitrogen atom is more electrons than that of the carbon atom.
Question number 6. "What volume of 15% (by mass) of the solution (C \u003d 1.10 g / ml) will be required for complete dissolution of the Al Al?"
Reaction equation:
Weight 1 l 15%:
1000 h 1,10 \u003d 1100g;
In 1100g 15% solution contains:
To dissolve 27G AL, it will be necessary:
Answer: a) 890ml.
Question number 7. "The reaction of hydrocarbon dehydrogenation is an endothermic process.
How to shift the reaction equilibrium: C4H10 (g)\u003e C4H6 (g) + 2H2 (d) in the direction of Education C4H6? " (Answer to give the form of the sum of the numbers corresponding to the selected methods): C4H10 (g)\u003e C4H6 (g) + 2H2 (g)10) increase the temperature;
Since the boutine dehydrogenation reaction is an endothermic process, it means that the system is heated (by increasing the temperature), the equilibrium is shifted towards the endothermic reaction, boutine formation (C 4 H 6).
50) lower pressure;
Gaseous substances are involved in the dehydrogenation reaction of Bhutan. The total number of moles of the starting substances is less than the total number of moles of the resulting gaseous substances, therefore, when the pressure decreases, the equilibrium shifts towards large volumes.
