Chemical Symbols

•A Chemical symbol is an abbreviation of a name of an element.

•Capital letter if only one letter.

•Only first letter capital if more than one letter

•Using standardized chemical symbols is important as each country, and language, have different words for each element.

•Sodium comes from the word sodanum, a headache remedy, and it’s symbol (Na) comes from the Latin word Natrium.

•A chemical formula is the combination of symbols that represent a particular compound.

•The chemical formula indicates which elements are present in the compound and in what amounts.

Ex. 1: Water molecule

H2O: 2 atoms of hydrogen, 1 atom of oxygen

Ex. 2: Iron Oxide molecule

Fe2O3: 2 atoms of iron, 3 atom of oxygen

•Each chemical symbol in a formula represents an element. If only one element is present in a compound, no number is included.

•

•If there is more than one atom of that element in the compound, the symbol is followed by a number written below the line. This number is called a subscript.