The periodic table is a table in which all of the known elements are listed. The table arranges the elements in order of increasing proton number to show the similarities of chemical elements. Therefore elements with structural similarities & atomic number are placed together. These elements can be placed into two different categories, metals & non-metals. These elements can then be sub divided into 4 groups; Alkali, non-metals, transition & inner-transitions. If read horizontally the size of the atoms increases from metals to non-metals, yet when read vertically, all of the elements in the same group have the same number of electrons, which means they all behave in the same manner.

The first man to describe the periodic table was Dmitri Ivanovich Mendeleev, whom was interested in chemistry. Mendeleev was determine to prove that elements in fact followed certain patterns. Mendeleev used the properties of the 57 known elements to group them. He used the first version of the periodic table to place elements where they seemed to belong. He also left blank spaces in the appropriate squares. After the elements had been laid out he was able to, in detail, predict the chemical & physical tendencies of the elements. Hydrogen didn’t fit into his pattern so he put it in a box of it’s own. A new row was started each time an element was discovered with properties similar to those in the first row. When read top to bottom there are various similarities to be found in the table, identicalas to when read left to right. This is the basis for the modern periodical table.

The elements in the periodic table are arranged in a manner that places them in order of increasing proton number in “Groups” which are the columns, & “Periods” which are the rows. There are 8 groups of electrons; each named by the number of electrons inside the outer shell of the atoms of the elements of