英语自学基础知识第267期

Put the outermost electron with the same number of elements according to the order of increasing number of electrons into a column from top to bottom.

The main family number = atomic number of the outermost electron number

2 structural features:

Type of nuclear outer electronic layer

12 elements of the first cycle

Short period 28 cycle second elements

Periodic third periodic 38 elements

418 cycles of fourth cycles (7 cycles)

Prime (7 cycles) fifth cycles of 518 elements

Cycle sixth cycle 632 elements

Seventh cycles of 7 cycles (there are 26 elements).

Table A: main group I ~ VII A a total of 7 main group

Family group: B, B III - VII I B - II B, a total of 7 sub group

(18 longitudinal) Group VIII: three longitudinal, located between B and B I VII

(16 people): neutral rare gas

Three, element periodic law

1. The periodic law of elements: the properties of the elements (nuclear outer electronic arrangement, atomic radius, valence, metal, non metal) with the nuclear charge number increases a cyclical changes in the rules. The properties of the elements the periodic variation in essence is the inevitable result of the periodic change of elements of the atom arrangement.

2 with the rule of changing periodic properties of the elements

Third 12Mg 15P 11Na 13Al 14Si 17Cl 16S 18Ar

(1) the number of the same electronic configuration of electronic, the outermost electron number increases

(2) the radius of the atomic radius decreases-

(3) + 1 + 2 + 3 4 main valence

4 5

3 +

2 7

1-

(4) metallic, metallic, metallic, non metallic-

(5) and pure water or acid replacement easy cold

Severe hot water and

Acid fast and acid reflux

Should be slow --

(6) PH3 H2S HCl SiH4-

(7) and H2. The difficult -- from difficult to easy -

(8) stability of the hydride generation - stability enhancement-

(9) MgO Al2O3 SiO2 P2O5 Na2O Cl2O7 SO3-

(10) Mg NaOH (OH) 2 Al (OH) 3 H3PO4 H2SO4 HClO4 H2SiO3-

(11) hydrogen acid alkali strong base amphoteric

Strong acid oxide

Strong acids

Acid-

(12) the change of the law of the law of the change of the law, and the increase of-

Na K A Li Rb Cs Fr (Fr is the strongest element, located in the left of the periodic table).

The seventh group A: F Cl Br I halogen At (F is the most nonmetallic elements in the periodic table, top right)

This method to determine the elements of metal and non-metallic strength:

(1) metal strong (weak) - 1 element and water or acid reaction generated hydrogen easy (difficult); II hydroxide alkaline strong (weak); (3) mutual replacement reaction (forced weak) Fe + CuSO4 = FeSO4 + Cu.

(2) non metal is strong (weak) - 1 element and hydrogen is easy (difficult) reaction; II generated hydride stability (instability); (3) the high valence oxide hydrate (containing oxygen acid) acid is strong (weak); (4) each other replacement reaction (forced weak) 2NaBr + Cl2 = 2nacl + Br2.

(I) the comparison of the same period:

Metal: Na > Mg > Al

React with acid or water: from easy to - > hard

Alkaline: NaOH > Mg (OH) 2, Al (OH) 3

Non metallic: Si < P < S < Cl

Elemental reaction and hydrogen: from easy to

Hydride stability: SiH4 < PH3 < H2S < HCl <

Acid (H2SO4):H2SiO3 < H3PO4 < HClO4 <<

(II) comparing with the main group:

Metal: Li < Na < K < Rb < Cs (alkali metal element)

The reaction with acid or water: from easy to

Basic: LiOH < NaOH < KOH < RbOH < CsOH non metallic: F > Cl > Br > I (halogen)

Elemental reaction and hydrogen: from easy to difficult

Hydride stability: HF > HCl > HBr > HI

(III)

Metal: Li < Na < K < Rb < Cs <

Reduction (K):Li < Na < Rb < Cs <<

Oxidation (electronic ability):Li >>>> Rb Na + K + CS + nonmetal: F > Cl > Br > I

Oxidation: F2 > Cl2 > Br2 > I2

<< F: reductive CL I < br

Acid (:HF < deoxygenated) HCl < HBr < HI

Comparison of particles (including atomic and ionic) radius of the method: (1) first to compare the number of electrons, the number of electrons in a large radius.

(2) electronic layers are the same, then compare the nuclear charge number, but a small radius of the nuclear charge number.

Four, chemical bond

Chemical bond is a strong interaction between two or more atoms.

Comparison between 1 ionic bond and covalent bond

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