To excel in Chemistry, memorizing the valency of chemical elements is crucial as it forms the fundamental basis for solving any chemistry-related problems. Here is the complete valency table for 8th-grade chemical elements, shared with you.

1. Some chemical elements
The valency of a chemical element is determined by the total number of chemical bonds it forms in a molecule.
The Valency Table comprises information about the number of protons, element names, chemical symbols, atomic masses, and valency, written in Roman numerals. In this article, Mytour shares the valency of some chemical elements found in the 8th-grade curriculum to help you reinforce fundamental chemistry knowledge.
MỘT SỐ NGUYÊN TỐ HÓA HỌC | ||||
Số proton |
Tên nguyên tố |
Ký hiệu hóa học |
Nguyên tử khối |
Hóa trị |
1 | Hiđro | H | 1 | I |
2 | Heli | He | 4 | |
3 |
Liti |
Li |
7 |
I |
4 |
Beri |
Be |
9 |
II |
5 |
Bo |
B |
11 |
III |
6 |
Cacbon |
C |
12 |
IV, II |
7 |
Nitơ |
N |
14 |
II, III, IV |
8 |
Oxi |
O |
16 |
II |
9 |
Flo |
F |
19 |
I |
10 | Neon | Ne | 20 |
|
11 |
Natri |
Na |
23 |
I |
12 |
Magie |
Mg |
24 |
II |
13 |
Nhôm |
Al |
27 |
III |
14 |
Silic |
Si |
28 |
IV |
15 |
Photpho |
P |
31 |
III, V |
16 |
Lưu huỳnh |
S |
32 |
II, IV, VI |
17 |
Clo |
Cl |
35.5 |
I, … |
18 | Argon | Ar | 39.9 |
|
19 |
Kaki |
K |
39 |
I |
20 |
Canxi |
Ca |
40 |
II |
24 |
Crom |
Cr |
52 |
II, III |
25 |
Mangan |
Mn |
55 |
II, IV, VII… |
26 |
Sắt |
Fe |
56 |
II, III |
29 |
Đồng |
Cu |
64 |
I, II |
30 |
Kẽm |
Zn |
65 |
II |
35 |
Brom |
Br |
80 |
I … |
47 |
Bạc |
Ag |
108 |
I |
56 |
Bari |
Ba |
137 |
II |
80 |
Thủy ngân |
Hg |
201 |
I, II |
82 |
Chì |
Pb |
207 |
II, IV |
Note:
Non-metal elements: text in green
Metal elements: text in black
Rare elements shine like red letters
2. Valency of some atomic groups of atoms
Besides the valency of common chemical elements, you need to equip yourself with the valency of some atomic groups of atoms to apply them more effectively in problem-solving.
HÓA TRỊ MỘT SỐ NHÓM CÁC NGUYÊN TỬ | ||||
Tên nhóm |
Hóa trị |
Gốc Axit |
Axit tương ứng |
Tính axit |
Hiđroxit (OH), Nitrat (NO3), Clorua (Cl) |
I |
NO3 |
HNO3 |
Mạnh |
Sunfat (SO4), Cacbonat (CO3) |
II |
SO4 |
H2SO4 |
Mạnh |
Photphat (PO4) |
III |
Cl |
HCl |
Mạnh |
(*): Tên này dùng trong các hợp chất với kim loại |
PO4 |
H3PO4 |
Trung bình |
|
CO3 |
H2CO3 |
Rất yếu (không tồn tại) |
3. The Valency Song - The fastest way to memorize the valency table
To aid your memory of the valency table, Mytour presents you with the valency song below:
Potassium, Iodine, Hydrogen
Sodium with silver, Chlorine in its own way
All with valency 1, oh dear friend
Remember to note it down clearly, or confusion may surround you
Magnesium, Lead, Zinc, Mercury
Calcium, Copper, they're also close to Bari
Finally, add dear Oxygen
Chemical bonding with valency 2, what challenges does it bring?
Uncle Aluminum has a trivalence, not once but thrice
Write deep in memory when needed right away
Carbon, Silicon right here
Valency 4, unforgettable every day
Iron there tells a familiar name
2, 3 up and down, truly annoying, alas
Nitrogen, the most troublesome in life
1, 2, 3, 4 as Thursday arrives
Sulfur, mischievous in playful times
Down to 2, up to 6 when lying on Wednesday
Phosphorus, talked about without excess
If anyone asks, just scoff and say 5
Hey, study hard, my dear
The periodic table song is crucial throughout the year.
4. Periodic Table

Complete table of chemical elements for 8th grade (Click on the image to view the original image)

Periodic table of chemical elements (Click on the image to view the original image)
Here is the valency table of chemical elements for 8th grade along with a valency song to help you remember better. Best wishes for your studies!