It's Elemental...
It's Elemental...


The Periodic Table

Dimitri Ivanovich Mendeleyev.  Born in 1834.  Rose to prominence in 1869.  Known for his wild hair and beard which he had trimmed just once a year  In 1869, he began to toy with a way to arrange the elements.  At the time, elements were normally grouped in one of two ways, by atomic weight or by common properties.  Mendeleyev’s breakthrough was to see that the two could be combined in a single table.  Mendeleyev place the elements into groups of seven when they appeared to repeat certain properties.  Because the properties repeated themselves periodically, the invention became known as the periodic table.

He arranged elements in horizontal rows called periods and vertical columns called groups (or families).  The instantly showed one set of relationships when read up and down, and another when read from side to side.  The vertical columns put together chemicals that have similar properties.  The horizontal rows arrange the chemicals in ascending order by the number of protons in their nuclei--what is known as their atomic number.

Today we have “120 or so” known elements--ninety two naturally occurring ones plus a couple of dozen that have been created in labs.  In Mendeleyev’s day just sixty-three elements were known, but part of his cleverness was to realize that the elements then known didn’t make a complete picture, that many pieces were missing. His table predicted, very accurately, where new elements would fit in when they were found.  No one knows how high the number of elements might go, but what is certain is that anything that IS found will fit neatly into Mendeleyev’s great scheme.