When the big bang happened, only the proton and neutron occurred. But if you see in the modern periodic table, there are 118 elements. I have wondered how this element comes, is it natural or man-made elements. Let’s get some crazy ideas on the periodic table. From 118 elements of the periodic table, 98 elements occurred naturally, and the rest 20 Elements were Man-made. So where did this element come from?Initially, after the big bang, the proton and neutron start to combine and make hydrogen nuclei and helium nuclei with different protons. When the solar system begins to cool down after the big bang, these nuclei start to capture electrons and become atoms. Interestingly, the Hydrogen atom condensed to form a star, and the hydrogen atom converted into a helium atom by the process called fusion reaction. Once the fusion reaction occurs, the energy has been released that tends to form elements. Depending upon the star size, fusion reaction energy can vary like it releases high energy in fusing smaller elements and small energy in fusing higher elements. Even though the big star can produce the elements till iron and fusion reaction stops at iron because iron is the most stable form of the nucleus. So where did the other elements come from?

Once the star reaches its age, the star eventually dies and leads to a supernova, white draft, or black hole, depending upon its mass. The explosive gives rise to other elements that we see in our periodic table. But, how did they arrange it in order?

The answer is quite simple. First, they thought of arranging it by metallic and non-metallic groups. Later German chemist Johann Wolfgang Döbereiner, in 1817 classified the elements as a triad. According to Döbereiner triad ideas, each element is arranged with increasing atomic mass. However, triad plans don’t fulfil other elements. But Döbereiner’s triad ideas gave a path to another chemist like John Newlands, Dmitri Ivanovich Mendeléev, etc. First, the English scientist John Newlands in 1866 arranged the elements with increasing atomic mass with hydrogen as the first atom. 

John Newlands also noted that every 8th element possesses similar properties and called the law the law of Octaves. However, after calcium, the 8th element doesn’t follow the rule. After discovering the noble gas law of Octaves has become irrelevant. Thus, the law of octaves works only for the lighter element. 

Later, Russian scientist Dmitri Ivanovich Mendeléev rearranged the periodic table with increasing atomic mass with the correlation of physical and chemical properties. 

It is worth mentioning that Dmitri Ivanovich Mendeléev predicted the element based on their properties and left space in between the periodic table and mentioned it as Sanskrit numeral, where few elements have to be discovered. Later some elements have been discovered and replaced the Sanskrit numeral. 

Even though the Dmitri periodic table has an advantage, it has its limitations such as no fixed position of hydrogen atom and isotopes have different atomic masses but same properties.

In 1913, English physicist Henry Moseley showed the atomic number (Z) of an element is a more important property than its atomic mass. Later, Henry Moseley modified Mendeléev’s Periodic table with atomic numbers.

It is worth mentioning that atomic number gives us the number of protons

in the nucleus of an atom and, this number increases by one from one element to the next. 

According to Henry Moseley, one group of elements will have the same number of valence electrons with Identical outer shell electrons. 

Few trends to remember in Modern Periodic Table

Valency– valency of the elements can be identified from the outermost shell of the atom.

Atomic size– Distance between the centre of the nucleus and the outermost shell of an isolated atom.

Metallic and non-metallic properties-a zig-zag line separates metals from non-metals with semimetals or metalloids at the borderline.