GRAM-MOLE

"An amount of a compound equal in grams to its molecular weight. E.g., the molecular weight of water is 18, so 18 grams of water is called a gram-mole of water. This provides an atomistically fundamental unit because one gram-mole of any material will contain the same number of molecules (this is a very large number, called ""Avogadro's"" number). One gram-mole of hydrogen gas contains the exactly same number of molecules as one gram-mole of table salt (sodium chloride), even though the latter is much heavier. The simplified expression of ""mole"" is often used in place of ""gram-mole"" and also in place of gram-atom. It is usually obvious from the context which meaning is appropriate. The measurement unit and symbol of the ""gram-mole"" or ""mole"" is the ""mol"". "