The atomic mass of elements is measured with the help of unified atomic mass units. One unified atomic mass unit can be quantified as the weight of one-twelfth of the mass of a carbon-12 atom considering that it is at rest. Since protons and neutrons account for almost all of the mass of the given atom, the atomic mass of a given element is almost equal to its mass number.
What is the Atomic Mass of Elements?
The atomic mass of an element can be described as
the total mass of one atom of the given element. Its unit is called the unified atomic mass unit and is denoted by the symbol ‘u’.
Standard atomic weight is used to give the value of the mean of the atomic masses in a mixture of isotopes in a given sample of an element.
Given below is a table that lists the first 30 elements based on atomic number and their corresponding atomic mass.
ATOMIC NUMBER
ELEMENT
ATOMIC MASS
1
Hydrogen
1.008
2
Helium
4.0026
3
Lithium
6.94
4
Beryllium
9.0122
5
Boron
10.81
6
Carbon
12.011
7
Nitrogen
14.007
8
Oxygen
15.999
9
Fluorine
18.998
10
Neon
20.180
11
Sodium
22.990
12
Magnesium
24.305
13
Aluminium
26.982
14
Silicon
28.085
15
Phosphorus
30.974
16
Sulfur
32.06
17
Chlorine
35.45
18
Argon
39.948
19
Potassium
39.098
20
Calcium
40.078
21
Scandium
44.956
22
Titanium
47.867
23
Vanadium
50.942
24
Chromium
51.996
25
Manganese
54.938
26
Iron
55.845
27
Cobalt
58.933
28
Nickel
58.693
29
Copper
63.546
30
Zinc
65.38
The Molecular mass of an element can be calculated by adding the atomic masses of each of its constituents. There are many ways to find the atomic mass of an element, but the easiest way is to look it up on the periodic table of elements.
Test your Knowledge on Atomic Mass of Elements!
Q5
Put your understanding of this concept to test by answering a few MCQs. Click ‘Start Quiz’ to begin!
Select the correct answer and click on the “Finish” button Check your score and answers at the end of the quiz
One Mole of a substance is defined as the total number of atoms in 12 grams of Carbon-12 isotope. It is denoted by ‘mol’ and is also referred to as gram molecular weight.
Frequently Asked Questions – FAQs
Q1
What is atomic mass?
Atomic mass is the average mass of the protons, neutrons, and electrons in an atom. Its unit is a unified atomic mass and is denoted by the symbol ‘u’.
Q2
What is one amu?
An Atomic mass unit or one amu is the mass unit equivalent to the one-twelfth mass of one atom of the carbon-12 isotope.
Q3
Why was carbon-12 selected as the reference element for calculating atomic mass?
Carbon-12 was chosen as a reference element for calculating atomic mass because it is naturally occurring and is present in abundance.
Q4
Is the one amu SI unit of atomic mass?
An Atomic mass unit or one amu is the physical constant accepted in the SI measurement system.
Q5
What is the full form of amu?
The atomic mass unit is the full form of amu. It is equivalent to the one-twelfth mass of one atom of the carbon-12 isotope.
If we are talking about the first 30 elements then the periodic table starts with Hydrogen and ends at Zinc that is an element with atomic number 30. These elements can be remembered by this line: Harley Health Like Beautiful Body of Cheetah Name Opposite Falcon Nest.
Since the combined masses of protons and neutrons account for almost all the mass of the given atom, the atomic mass of a single atom can be calculated by adding the total number of protons and the total number of neutrons of that particular isotope.
You could use the acronym HHeLiBeBCNOF (pronounced 'heeliebeb kernoff') to remember the first nine chemical elements. It's a nonsense word, but it condenses nine names into one mental prompt or cue. Or the acrostic “Here He Lies Beneath Bed Clothes, Nothing On, Feeling Nervous” would equate to H He Li Be B C N O F Ne.
Oganesson has the highest atomic number and highest atomic mass of all known elements as of 2024. On the periodic table of the elements it is a p-block element, a member of group 18 and the last member of period 7.
Mass number is a whole number because it is the sum of number of protons and number of neutrons whereas atomic mass is fractional because it is the average relative mass of its atoms as compared with mass an atom of C−12 isotope taken as 12.
Address: Apt. 994 8891 Orval Hill, Brittnyburgh, AZ 41023-0398
Phone: +26417467956738
Job: District Marketing Strategist
Hobby: Embroidery, Bodybuilding, Motor sports, Amateur radio, Wood carving, Whittling, Air sports
Introduction: My name is Prof. An Powlowski, I am a charming, helpful, attractive, good, graceful, thoughtful, vast person who loves writing and wants to share my knowledge and understanding with you.
We notice you're using an ad blocker
Without advertising income, we can't keep making this site awesome for you.
