How students should use it
Write the charge for each ion first, then reduce the ratio until the total charge is zero.
Ionic Compounds Worksheet
Practice using ion charges to write neutral ionic formulas.
Worksheet answer key
| Positive ion | Negative ion | Answer |
|---|---|---|
| magnesium | oxygen | MgO |
| aluminum | chloride | AlCl3 |
| calcium | nitrate | Ca(NO3)2 |
| sodium | sulfate | Na2SO4 |
| iron(III) | oxide | Fe2O3 |
| copper(II) | chloride | CuCl2 |
Common mistake
Do not change the formula inside a polyatomic ion. Add parentheses when more than one copy is needed.
When to check the chart
Use the charge chart for transition metals and polyatomic ions before writing the final formula.