Lesson 20

As lesson 19 told us, elements bond with one another in a fashion that creates a neutral charge (0.) This requires the presence of cations, positively charged atoms, and anions, negatively charged, and when we have a scenario like this, we get an ionic bond. Ionic bonds typically occur between metals and nonmetals in the periodic table. The electrons in ionic compounds are "stolen" by the atom that has more valence electrons in order to create its full outer shell, and the other atom tags along. When you have an ionic compound between a metal and a nonmetal, you change the ending of the nonmetal's name to -ide. For example, NaCl is sodium chloride, not sodium chlorine.

Problems:
2.) How does the rule of zero charge help you predict the formula of an ionic compound? You can look at the two atoms you are presented with and consider their charges. If Lithium (Li) has a charge of +1, you would write it as Li^+1 (where the ^ tells you that +1 should be a superscript). If You wished to combine it with Fluorine, F, which has a negative charge, you would write the compound as Li^+1F^-1. An easy trick to use is to put the superscript (little number above) of the Fluorine atom as the subscript (little number below) of the Lithium atom, which would tell you that you only had 1 atom of Lithium. In this, you have a negative charged and a balanced chemical compound.

7.) Explain why these compounds do not form:
a.) NaCl2 - If this compound occured, it would not be balanced because it would have a negative charge. In other words, you would have too many chlorine atoms and your delicious table salt would be no more.
b.) CaCl - You would have a great deal of trouble balancing this one, since the chlorine atom, with 7 valence electrons, cannot accommodate Ca's 2. You'd have to give and take Ca and Cl atoms until you came up with a net charge of 0.
c.) AlO - Same with CaCl. You would have too many charges in the aluminum atom to fit with the oxygen atom and matching the charges would be tedious.