FORMULA WINDOW


     The Formula window contains a number of buttons, which are used to define the formula.  These buttons include a collection of Element buttons, which together form a subset of the Periodic Table of the Elements.  The reduced table only contains buttons for elements that are involved in VSEPR-type bonding (i.e., non-metals, metalloids, noble gases and beryllium, the one metal that partakes in covalent bonding).  The buttons on the table also include a Clear button, Plus and Minus Ion buttons and a Model button.  In addition to these buttons, the Formula window contains a display line, in which the formula appears as it is being defined.