Question

Атомная масса первых 20 элементов

Answer 1

1 Н - 1гр

2 Не - 4гр

3 Li - 7

4 Be - 9

5 B - 11

6 C -12

7 N -14

8 O -16

9 F -19

10 Ne -20

11 Na -23

12 Mg -24

13 Al -27

14 Si-28

15 P-31

16 S-32

17 Cl-35

18 Ar-40

19 K-39

20 Ca-40

Answer 2

The atomic masses of the first 20 elements of the periodic table are as follows:

1. Hydrogen (H) - 1.008
2. Helium (He) - 4.0026
3. Lithium (Li) - 6.94
4. Beryllium (Be) - 9.0122
5. Boron (B) - 10.81
6. Carbon (C) - 12.01
7. Nitrogen (N) - 14.01
8. Oxygen (O) - 16.00
9. Fluorine (F) - 19.00
10. Neon (Ne) - 20.18
11. Sodium (Na) - 22.99
12. Magnesium (Mg) - 24.31
13. Aluminum (Al) - 26.98
14. Silicon (Si) - 28.09
15. Phosphorus (P) - 30.97
16. Sulfur (S) - 32.06
17. Chlorine (Cl) - 35.45
18. Argon (Ar) - 39.95
19. Potassium (K) - 39.10
20. Calcium (Ca) - 40.08

Please note that these values are approximate and can slightly vary depending on the source and the most recent atomic mass data available at the time of your inquiry.