Predict the empirical formulas of the ionic compounds formed from the following pairs of elements. Name each compound. a. \(\mathrm{Al}\) and \(\mathrm{Cl}\) c. \(\mathrm{Sr}\) and \(\mathrm{E}\) b. \(\mathrm{Na}\) and \(\mathrm{O}\) d. \(\mathrm{Ca}\) and \(\mathrm{Se}\)

Determine the charges of the ions from their group number in the periodic table. Notice that elements in group 1 (alkali metals) form ions with a +1 charge, group 2 (alkaline earth metals) form ions with a +2 charge, and elements in group 17 (halogens) form ions with a -1 charge. Elements in group 16 form ions with a -2 charge.

Balance the overall charge by finding the simplest ratio of ions in each empirical formula. This is done by crossing the absolute values of the charges.

Name each compound using the rules for naming binary ionic compounds. This includes using the full name of the metal followed by the root of the second element's name, ending in "ide." Now, let's apply these steps to the given pairs of elements. a. Al and Cl - Step 1: Al forms a 3+ ion, while Cl forms a 1- ion. - Step 2: Empirical formula is AlCl3. - Step 3: Name the compound Aluminum Chloride. b. Na and O - Step 1: Na forms a 1+ ion, while O forms a 2- ion. - Step 2: Empirical formula is Na2O. - Step 3: Name the compound Sodium Oxide. c. Sr and E is likely an error. It should be Sr and I (Strontium and Iodine). - Step 1: Sr forms a 2+ ion, while I forms a 1- ion. - Step 2: Empirical formula is SrI2. - Step 3: Name the compound Strontium Iodide. d. Ca and Se - Step 1: Ca forms a 2+ ion, while Se forms a 2- ion. - Step 2: Empirical formula is CaSe. - Step 3: Name the compound Calcium Selenide.