7.6.B:  use the periodic table to identify the atoms and the number of each kind within a chemical formula

Identify

THE ATOMS AND THE NUMBER OF EACH KIND WITHIN A CHEMICAL FORMULA USING THE PERIODIC TABLE OF ELEMENTS

Including, but not limited to:

• Chemical formula – identifies the elements in a compound and the proportions or ratios of the elements

  • Each type of element in the compound is represented by its chemical symbol.

    • The periodic table of elements can be used to look up the name of an element using its chemical symbol.

      • CO – carbon monoxide

        • C = carbon

        • O = oxygen

      • NaCl – sodium chloride

        • Na = sodium

        • Cl = chlorine

  • The proportion (ratio) of each element in a compound is constant.

    • The number of atoms represented by specific ratios as determined by subscripts

    • If there is no subscript present, a single atom of that element is present in the molecule.

      • CO2 – carbon dioxide

        • C = one carbon atom

        • O2 = two oxygen atoms

      • H2O – water

        • H2 = two hydrogen atoms

        • O = one oxygen atom

      • C6H12O6 – glucose

        • C6 = six carbon atoms

        • H12 = twelve hydrogen atoms

        • O6 = six oxygen atoms