The relative atomic masses of the first 20 members of the periodic table

Hydrogen, helium, lithium, beryllium, boron, carbon, nitrogen, oxygen, fluorine, neon, sodium, magnesium, aluminum, silicon, phosphorus, sulfur, chlorine, argon, potassium, calcium.

1 hydrogen h 1

2 helium he 4

3 Lithium li 7

4 Beryllium be 9

5 Boron b 11

6 C12

7 N 14

8 Oxygen o 16

9 Fluoro f 19

10 Neon ne 20

11 Sodium Na 23

12 mg 24

13 Al-27

14 Si Si 28

15 P p 31

16 Sulfur S32

17 Cl chloro

18 argon ar 40

19 potassium k 39

20 Calcium Ca40

Hydrogen, helium, lithium, beryllium, boron, carbon, nitrogen, oxygen, fluorine, neon, sodium, magnesium, aluminum, silicon, phosphorus, sulfur, chlorine, argon, potassium, calcium.

Feel free to ask, dear.

Schematic diagram of the atomic structure of elements 1 to 20.

As follows: <>

The schematic diagram of the atomic structure of elements 20 to 30 is as follows:

Elements one to twenty are as follows:

1-5: H hydrogen, HE helium, LI lithium, BE beryllium, B boron.

6-10: C carbon, N nitrogen, O oxygen, F fluorine, ne neon.

11-15: Na sodium, mg magnesium, Al aluminum, Si silicon, P phosphorus.

16-20: S sulfur, Cl chlorine, Ar argon, K potassium, Ca calcium.

1. Hydrogen qīng

2. Helium hài

3. Lithium lǐ

4. Beryllium pí

5. Boron péng

6. Carbon tàn

7. Nitrogen dàn

8. oxygen yǎng

9. Fluorine dust fú

10. Neon nǎi

11. Sodium nà

12. Magnesium měi

13. Aluminum lǔ

14. Silicon gūi

15. Phosphorus líng

16. Sulfur liú

17. Chlorine lù

18, argon yà

19, potassium jiǎ

20. Calcium gài

21, scandium kàng

22. Titanium tài

23. Vanadium fán

24. Chromium gè

25. Manganese měng

26, iron tiě

27, cobalt gū

1. An element is a general term for a class of atoms with the same nuclear charge number (proton number) 2. Different atoms of the same element are called isotopes to each other, and their proton numbers are different 3. A certain isotope can be called a nuclide.

4. The same is true for the elements in the periodic table, such as the carbon element c, which represents all atoms with a nuclear charge number (proton number) of 6.

1. Hydrogen (h).

2. Helium (He).

3. Lithium (Li).

4. Beryllium (BE).

5. Boron (b).

6. Carbon (c).

7. Nitrogen (n).

8. Oxygen (O).

9. Fluorine (f).

10. Neon (ne).

11. Sodium (Na).

12. Magnesium (mg).

13. Aluminum (AL).

14. Silicon (Si).

15. Phosphorus (P).

16. Sulfur (s).

17 Cl chloro

18. Argon (ar).

19. Potassium (k).

20. Calcium (ca).

The periodic table of chemical elements is a list of chemical elements sorted from smallest to largest according to their atomic number. The list is generally rectangular in shape, with spaces in the period of some elements, so that elements with similar characteristics are grouped into the same family, such as alkali metal elements, alkaline earth metals, halogen elements, rare gases, etc.

Extended Materials. Element position inference.

1. The number of element periods is equal to the number of electron shells outside the nucleus;

2. The ordinal number of the main group elements is equal to the number of outermost electrons;

3. To determine the number of families, we should first determine whether it is the main family or the secondary family, and the method is to use the atomic number to gradually subtract the number of elements in each period, which can be determined by the final difference.

In the first to fifth cycles, when the final difference is less than or equal to 10, the difference is the family ordinal, when the difference is , it is the family, and when the difference is greater than 10, then subtract 10, and the final result is the family ordinal;

In the section. The difference between the six and seven cycles is 1: group a, and the difference is 2:

A group, the difference is 3 17: lanthanide or actinides, the difference is between 18 and 21: minus 14, the difference is 22 24:

Family, the difference is greater than 25: minus 24, which is the corresponding main family.

According to the inference of the types of elements contained in each period, the atomic number is subtracted by the number of elements contained in each period, and when the result is "0", it is the zero group. When it is a positive number, it is the vertical row of the number from left to right in the periodic table, and if it is "2", it is the second vertical row of the number from left to right in the periodic table, that is, the group a; When negative, its main family ordinal is 8+ result.

A table of the relative atomic masses of commonly used elements, as shown in the figure below:

The top 20 chemical elements in the periodic table of chemical elements:

Hydrogen (qīng) helium (hài) lithium (lǐ) beryllium (pí) boron (péng) carbon (tàn) nitrogen (dàn) oxygen (yǎng) fluorine (fú) neon (nǎi) sodium (nà) magnesium (měi) aluminum (lǚ) silicon (guī) phosphorus (lín) sulfur (liú) chlorine (lǜ) argon (yà) potassium (jiǎ) calcium (gài).

Different atomic masses of the same element are not the same, and the relative atomic mass of an element in the periodic table is the average of the relative masses of different atoms of the same element in a certain proportion. The mass of the atom of the same element is somewhat the same, and some are different, depending on the number of neutrons.