Final Chemistry Notebook

Non-metals, which lack only one or two electrons in the outer energy level have little tendency to
lose electrons - the ionization potential would be very high. Instead non-metals have a tendency to
gain electrons. The ELECTRON AFFINITY is the energy given off by an atom when it gains
electrons.
Non-metal Atom + e- --- Non-metal (-) ion + energy
The energy required to produce positive ions (ionization potential) is roughly balanced by the energy
given off to produce negative ions (electron affinity). The energy released by the net force of
attraction by the ions provides the overall stabilizing energy of the compound.
https://www.youtube.com/watch?v=zpaHPXVR8W U
Writing Ionic Compounds
An easy technique for creating a neutral combination of two charged ions is called the criss-cross
technique. When writing a formula for an ionic compound the charges from each ion are simply
switched to become the subscript values written to designate the number of atoms present in a
compound. See the example below.
Naming Ionic Compounds
Naming Binary Ionic Compounds
Learning to name ionic compounds is both easy and hard depending on the complexity of the
compound. Before we start, though, I just wanted to review a few terms. Remember that positively
charged ions are called cations. Negatively charged ions are called anions. An ionic compound is a
compound held together by ionic bonds. A simple binary compound is just what it seems - a simple
compound with two elements in it.
Binary compounds are easy to name. The cation is always named first and gets its name from the
name of the element. For example, K + is called a potassium ion. An anion also takes its name from
its element, but it adds the suffix -ide to it. So, Cl - is called a chloride ion; O 2- is an oxide ion.
Take the binary compound NaCl. The Na + is a sodium cation. The Cl - is a chlorine anion, which
gets the suffix -ide added to it. When you put them together, it becomes sodium chloride. Here are
some examples for you:
Zn 2+ is zinc. S 2- is sulfide. Put them together for zinc sulfide (ZnS).
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