Periodic Table: Elemental Information

The periodic table is a chart of the elements arranged so that their physical and chemical properties can be deduced. Each element is identified by its atomic symbol, a one, two or three letter abbreviation. Often these letters are similar to an elements name, but some of the symbols, like Fe for iron, are from Latin. Some versions of the periodic table list both the symbol and the name of the element. The elements are arranged by increasing atomic number, which is the number of protons in an atom of that element. The atomic number is an integer, since the number of protons must be a whole number. Another piece of information found on most periodic tables is the atomic weight (also called the atomic or molar mass). This number is the weighted average of the masses of the naturally occurring isotopes of that element. The atomic weight is not an integer.

Concept Check: Use the link in the paragraph above to go to the periodic table page. Find tin, Sn. What is the atomic number of tin? Where does Sn come from?

Answer: Tin has an atomic number of 50. The atomic symbol comes from the Latin name for tin, stannum, which means alloy of lead.

This site was last updated 08/01/06