Atomic Mass and Number of First 13 Elements in the Periodic Table
BY Team Aakash Byju's
The atomic number of a chemical element is the number of charges carried by its atomic nucleus.
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The number of protons and neutrons of an atom is called ‘Atomic Mass’. The atomic mass is expressed in terms of ‘atomic mass unit’(amu).
Hydrogen is the first element of the periodic table with atomic number 1 and an atomic mass of
1.00797 amu.
Helium follows Hydrogen in the periodic table. Its atomic number is 2 & atomic mass is
4.00260 amu.
The third element of the periodic table is Lithium (Li), whose atomic number is 3 and atomic mass of 6.941 amu.
Beryllium & Boron are the next elements in the periodic table with atomic numbers 4 & 5, and atomic mass 9.0122 amu & 10.8 amu respectively.
The element with atomic number 6 and atomic mass of 12.011 amu is called ‘Carbon’.
Nitrogen has atomic number 7, and it has an atomic mass of
14.007 amu.
The atomic number of Oxygen (O) = 8, and the atomic mass of
O = 15.9994 amu.
The 9 & 10 are the atomic numbers of Fluorine & Neon with respective atomic masses of 18.998403 amu and
20.179 amu.
Fluorine
Neon
Sodium with atomic number 11 has an atomic mass of 22.98976 amu.
The atomic number of the next element Magnesium is 12, and it has an atomic mass of 24.305 amu.
Aluminium being the next element in the table has an atomic number 13 and atomic mass of 26.982 amu.
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