It's
Elemental...
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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.
The atoms in any particular element are exactly the same as
every other atom on that element. They cannot be broken
down into simpler substances. The number of protons
determines the elements chemical and physical properties.
The Electrons are used in bonding one atom to another to
form. These combinations of atoms, called Molecules, form
every single bit of matter in the universe. Simply by changing
the "recipe", the very same atoms can be rearranged to make
something completely different. Think of it, YOU are made
from the very same atoms from which a slice of bread is made, or
a rock, or a dinosaur, or a drop of rainwater. The only
thing different between your atoms and those other atoms is the
particular recipe that was followed to make you, or those other
things.