Hydrogen (H) and fluorine (F) each have a valence of 1, and generally these will not be central atoms (bonded to more than one atom). Choose a central atom (we will take as examples small molecules for which there is only one central atom, and the other atoms, the peripheral atoms, are all attached to the central atom). Which will help us decide how the atoms will bond. The second step is to draw a skeletal structure.For polyatomic ions, add the valence electrons of all atoms in the formula and subtract one electron for each positive charge on a cation and add one electron for each unit negative charge on an anion. One way to do such a count is to write Lewis symbols for all the atoms in the formula and count all the “dots.” For an (uncharged) molecule, that count is the correct number of valence electrons. First, it is important to get a correct count of all the valence electrons.Given a chemical formula corresponding to a molecule or molecular ion, the steps to obtain its Lewis structure are as follows:
0 Comments
Leave a Reply. |