The problem of the list of chemical elements is urgent

After the combination of atom A 1mol and atom D atom 1mol to form an electron shell is 2,8 structure, then the compound formed by a and d must be in a one-to-one form, that is, AD form.

In the same way, BC is also one-to-one, and requires ABCD to decrease in atomic number.

There must be two metals and two non-metals, and the two non-metals are of the second cycle and the two non-metals are of the second cycle.

Hence the inference.

a--mgb--na

c--fd--o

ABCD should be an element around neon atoms.

c n o f ne na mg al si, so it is mg na f o

However, al mg o n, al na f n should also work, but the above one is the best.

First of all, as mentioned in the title, they all transfer electrons at 1:1, so the matter formed should be a structure like AB.

Around the neon element, in turn is nitrogen oxyfluorone, sodium neon, magnesium, aluminum, silicon, because it is a 1:1 reflection, so it should be sodium chloride and magnesium oxide. By the title, ABCD ordinal decreasing, so A is magnesium, B is sodium, C is fluorine, and D is oxygen.

The ABCD element is apparently in the vicinity of neon.

Conjecture validation. In fact, it can also be a:al b:mg c:o d:na:al b:na c:f d:n

It's all symmetrical.

But it's better to write a:mg b:na c:f d:o (common) over).

Hydrogen(H) hydrogen.

helium (he) helium.

lithium (li).

beryllium(BE) beryllium.

boron(b)

Boron. carbon(c) carbon.

Nitrogen (N) Nitrogen tung split.

oxygen(o) oxygen.

Fluorine (f) fluorine.

neon (neon).

Sodium(Na) sodium.

magnesium (mg).

Aluminium (Al) aluminum.

Silicon (Si).

phosphorus(p) phosphorus.

sulfur(s) sulfur.

chlorine (Cl) chlorine.

Argon(ar) argon bureau closed.

potassium (k).

Calcium (CA) calcium.

gold (AU).

Silver (AG) silver.

copper (cu).

Iron (Fe).

Zinc (ZN).

Manganese (MN) manganese.

mercury (hg).

Barium (ba).

Bromine (br) bromine.

iodine (i) iodine.

-+H2O, so the answer is: al2O3+2oh- 2alo2-+H2O;

7) The common liquid compound composed of the atoms of the two elements in the table at 1:1 is H2O2, which is catalyzed by FeCl3 or Mno2 to form O2, so the answer is: AB

h Hydrogen 1

he helium 4

Li Lithium. beryllium.

b boron c carbon 12

n Nitrogen 14

o Oxygen 16

f Fluorine neon.

Na sodium 23

mg Magnesium 24

al Aluminium 27

si silicon. P phosphorus 31

s sulfur-32

Cl chlorine. ar argon.

k Potassium 39

CA Calcium 40

Fe Fe 56

Cu Copper 64

Zn Zinc 65

ba barium 137

au gold. ag silver.

Hg mercury.

The periodic table has 7 periods and 16 families.

Each horizontal row is called a cycle, and each vertical row is called a family.

These 7 cycles can be divided into short cycles and long cycles). There are 16 families, which are divided into 7 main families ( a a a), 7 sub families ( b b), one first family (including three vertical rows), and one zero family.

Group 0 elements on the periodic table belong to noble gases (noble gases). At room temperature and pressure, they are all colorless and odorless monoatomic gases, which are difficult to carry out chemical reactions. There are seven noble gases, which are helium (He), neon (Ne), argon (Ar), krypton (Krypton), xenon (Xe), radon (RN, radioactive), and gas (OG, radioactive, man-made element).

Periodic Table of Chemical Elements: A list of chemical elements sorted from smallest to largest according to their atomic number.

A bit vague but hope it helps.

A chemical element is a general term for a class of atoms that have the same number of nuclear charges (i.e., the number of protons in the nucleus). From a philosophical point of view, it is the result of a qualitative change caused by a quantitative change in the number of electrons in an atom.

Chemical element refers to more than 100 basic metal and non-metal substances in nature, which are composed of only one kind of atom, and each nucleon in its atom has the same number of protons, which cannot be decomposed by ordinary chemical methods, and can constitute all substances. Some examples of common elements are hydrogen, nitrogen, and carbon.

As of 2012, a total of 118 elements have been discovered, 94 of which are found on Earth. Elements with atomic numbers greater than 83 (i.e., after bismuth) are unstable and will undergo radiative decay. The 43rd and 61st elements, i.e., technetium and promethium, have no stable isotopes and undergo decay.

However, even elements with atomic numbers as high as 95 and no stable nuclei can be found in nature, which is the natural decay of uranium and thorium.