Atomic Mass of Elements | Atomic Mass and Valency of First 30 Elements

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Atomic Mass of Elements: You can find the atomic mass of elements list below. If you want to remember the atomic mass of the elements, here’s a useful list of elements by atomic mass. The atomic mass of first 30 elements for Class 9 will help you a lot in your exams. This page also includes the common valencies of the first 30 elements for quick revision. For more Class 9 study resources, you can also explore the latest resources on Topper’s Social Science.

Quick Revision: Learn the element name, symbol, atomic number, approximate atomic mass and common valency together. This makes revision much easier than memorising each value separately.
Atomic Mass and Valency of First 30 Elements

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 Atomic Number Atomic Mass Common Valency
Hydrogen111
Helium240
Lithium371
Beryllium492
Boron5113
Carbon6124
Nitrogen7143
Oxygen8162
Fluorine9191
Neon10200
Sodium11231
Magnesium12242
Aluminium13273
Silicon14284
Phosphorus15313, 5
Sulfur16322, 4, 6
Chlorine1735.51, 3, 5, 7
Argon18400
Potassium19391
Calcium20402
Scandium21453
Titanium22482, 3, 4
Vanadium23512, 3, 4, 5
Chromium24522, 3, 6
Manganese25552, 4, 7
Iron26562, 3
Cobalt27592, 3
Nickel2858.72, 3
Copper2963.51, 2
Zinc30652

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.

Important: For many of the first 20 elements, valency can be understood from the number of electrons in the outermost shell. Elements with a complete outer shell, such as helium, neon and argon, generally have valency 0.

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.

Elements with more than one common valency

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.

Exam Tip: Do not confuse valency with oxidation number. They are related concepts, but they are not identical in every chemical situation.

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.

01 Learn the elements Start with the names and symbols of elements 1 to 30.
02 Remember atomic numbers Practise the sequence from 1 to 30 until it becomes familiar.
03 Practise atomic masses Focus first on the commonly used approximate values.
04 Revise common valencies Pay special attention to elements that show multiple valencies.
05 Test yourself Cover the table and recall the values without looking.
Quick Revision Tip: Revise the first 10 elements together, then 11–20, and finally 21–30. After learning each group, test yourself before moving to the next group.
Free Study Resource

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.

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Frequently Asked Questions

What is the atomic mass of the first 30 elements?

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.

What is the atomic number of an element?

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.

What is the valency of the first 30 elements?

The common valencies of the first 30 elements are given in the main table above. Some elements can show more than one common valency.

What is the difference between atomic number and atomic mass?

Atomic number identifies an element through its number of protons, whereas atomic mass represents the relative mass of its atoms.

Which elements among the first 30 show common multiple valencies?

Several elements, particularly some transition elements and elements such as nitrogen, phosphorus, sulfur and chlorine, can show more than one common valency.

How can I remember the first 30 elements?

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.

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RecallClose the page and explain the main idea in your own words.
PractiseMove to MCQs and important questions after studying.
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