| Sodium is in the first column of the periodic table, so it loses one
electron and becomes a sodium ion with a +1 charge. Iodine is a nonmetal in the next to
the last column so it will take on a -1 charge and is called a iodide ion. So we have a +1 charge for sodium and a -1 charge for
iodine. The charges are
opposite but equal; therefore, there is a 1:1 ratio of sodium ions to
iodide ions and NaI is the formula of the compound. The name of this ionic compound is
sodium iodide because it is made of sodium ions and iodide ions. |
| Ions |
Na+ |
I- |
| Charge ratio |
1 |
1 |
| Ion ratio |
1 |
1 |
| Formula |
NaI |
| Name |
sodium iodide |
|
