Atomic Mass of the First 30 Elements: Use this page as a quick reference for the first 30 elements with symbols, atomic numbers, approximate atomic masses and common valencies. It is designed for Class 9 Science/Chemistry revision, especially when you are learning atoms, chemical formulae and valency. The table uses rounded, school-friendly values for quick revision; exact standard atomic-weight values can be more precise. For more Class 9 study resources, explore the wider Topper’s Social Science library.
First 30 Elements — Quick Answers
Atomic Mass and Valency of First 30 Elements
The table below gives the names, symbols, atomic numbers, approximate atomic masses and common valencies of the first 30 elements. It is useful for Class 9 Chemistry revision and for learning how atomic number and valency are related.
| Element | Symbol | Atomic Number | Atomic Mass | Common Valency |
|---|---|---|---|---|
| Hydrogen | H | 1 | 1 | 1 |
| Helium | He | 2 | 4 | 0 |
| Lithium | Li | 3 | 7 | 1 |
| Beryllium | Be | 4 | 9 | 2 |
| Boron | B | 5 | 11 | 3 |
| Carbon | C | 6 | 12 | 4 |
| Nitrogen | N | 7 | 14 | 3 |
| Oxygen | O | 8 | 16 | 2 |
| Fluorine | F | 9 | 19 | 1 |
| Neon | Ne | 10 | 20 | 0 |
| Sodium | Na | 11 | 23 | 1 |
| Magnesium | Mg | 12 | 24 | 2 |
| Aluminium | Al | 13 | 27 | 3 |
| Silicon | Si | 14 | 28 | 4 |
| Phosphorus | P | 15 | 31 | 3, 5 |
| Sulfur | S | 16 | 32 | 2, 4, 6 |
| Chlorine | Cl | 17 | 35.5 | 1, 3, 5, 7 |
| Argon | Ar | 18 | 40 | 0 |
| Potassium | K | 19 | 39 | 1 |
| Calcium | Ca | 20 | 40 | 2 |
| Scandium | Sc | 21 | 45 | 3 |
| Titanium | Ti | 22 | 48 | 2, 3, 4 |
| Vanadium | V | 23 | 51 | 2, 3, 4, 5 |
| Chromium | Cr | 24 | 52 | 2, 3, 6 |
| Manganese | Mn | 25 | 55 | 2, 4, 7 |
| Iron | Fe | 26 | 56 | 2, 3 |
| Cobalt | Co | 27 | 59 | 2, 3 |
| Nickel | Ni | 28 | 58.7 | 2, 3 |
| Copper | Cu | 29 | 63.5 | 1, 2 |
| Zinc | Zn | 30 | 65 | 2 |
Atomic Number and Atomic Mass of the First 30 Elements
Atomic number and atomic mass are two different properties of an element. Understanding the difference between them is important before learning atomic structure and chemical formulae.
What is Atomic Number?
The atomic number is the number of protons present in the nucleus of an atom. In a neutral atom, the number of electrons is also equal to the atomic number.
What is Atomic Mass?
Atomic mass represents the relative mass of an atom. It is based mainly on the combined contribution of protons and neutrons in the nucleus.
Atomic Number vs Atomic Mass
| Term | What it tells us | Example |
|---|---|---|
| Atomic Number | Number of protons present in the nucleus | Hydrogen = 1 |
| Atomic Mass | Relative mass of an atom, mainly related to protons and neutrons | Carbon ≈ 12 |
| Symbol | Short representation of an element | Hydrogen = H |
What is Valency?
Valency indicates the combining capacity of an element. It is related to the number of electrons an atom loses, gains or shares while forming chemical compounds.
Common Valencies of the First 30 Elements
Some elements have more than one common valency. Therefore, while revising the table, pay particular attention to elements such as nitrogen, phosphorus, sulfur, chlorine and several transition elements.
Nitrogen, phosphorus, sulfur, chlorine, titanium, vanadium, chromium, manganese, iron, cobalt, nickel and copper can show more than one common valency. The exact valency depends on the compound and the chemical context.
Valency Pattern to Remember
For the first 20 elements, valency follows a useful pattern across the periods: 1, 0, 1, 2, 3, 4, 3, 2, 1, 0 for H–Ne and 1, 2, 3, 4, 3, 2, 1, 0 for Na–Ar. This pattern is often easier to recall than memorising every value separately. From scandium onward, several transition elements can show more than one common valency.
How to Revise the First 30 Elements
Memorising 30 elements becomes easier when you divide the information into small groups instead of trying to learn everything at once.
Reference & Curriculum Context
This page is a student-friendly reference rather than an official CBSE data sheet. The terminology and study context were checked against the CBSE Academic 2026–27 curriculum portal and CBSE Science learning material. For school work, follow the values and conventions used by your textbook or teacher when a question specifies a particular value.
Download Atomic Mass of Elements PDF
Save a printable revision copy of the atomic masses and valencies of the first 30 elements for quick exam preparation.
Planning Ahead for Class 10?
This page is focused on Class 9 Chemistry. If you are also preparing for Class 10 Social Science, these dedicated resources are available separately so you can move to the right subject at the right time.
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Frequently Asked Questions
The atomic masses of the first 30 elements range from about 1 for hydrogen to about 65 for zinc. The complete reference table is provided above.
Atomic number is the number of protons present in the nucleus of an atom. In a neutral atom, it is also equal to the number of electrons.
The common valencies of the first 30 elements are given in the main table above. Some elements can show more than one common valency.
Atomic number identifies an element through its number of protons, whereas atomic mass represents the relative mass of its atoms.
Several elements, particularly some transition elements and elements such as nitrogen, phosphorus, sulfur and chlorine, can show more than one common valency.
Learn the elements in groups of ten and revise their symbols, atomic numbers, atomic masses and common valencies together. Regular self-testing makes recall easier.