Question

An ionic compound of potassium and oxygen has the empirical formula KO. Would you expect this compound to be potassium(II) oxide or potassium peroxide? Explain.

Short answer

The given compound (KO) has potassium with an oxidation state of +1 and oxygen with an oxidation state of -1. Comparing this with the known compounds potassium(II) oxide (K2O) and potassium peroxide (K2O2), the compound matches the composition and oxidation states of potassium peroxide (K2O2). Therefore, the ionic compound of potassium and oxygen with the empirical formula KO is potassium peroxide (K2O2).

Step-by-step solution

Identify the oxidation state of potassium and oxygen in the given compound

The oxidation state of potassium (K) in the given empirical formula (KO) is +1 since it belongs to Group 1 in the periodic table. The oxidation state of oxygen (O) in the compound is -1, as the total charge of the compound must be neutral.

Compare the given compound with the known compounds potassium(II) oxide and potassium peroxide

Potassium(II) oxide (K2O) has the following oxidation states: potassium has an oxidation state of +1 (each potassium ion) and oxygen has an oxidation state of -2. This means there are two potassium ions for each oxygen ion in the compound. Potassium peroxide (K2O2) has the following oxidation states: potassium has an oxidation state of +1 (each potassium ion) and each oxygen in the peroxide ion (O2^2-) has an oxidation state of -1. So there are two potassium ions and one peroxide ion (which contains two oxygen atoms) in this compound.

Determine the identity of the given compound based on the comparison

From Step 1, we determined that the given compound (KO) has potassium with an oxidation state of +1 and oxygen with an oxidation state of -1. Comparing this with the oxidation states found in Step 2, we can conclude that the given compound matches the composition and oxidation states of potassium peroxide (K2O2). Therefore, based on the information provided and our analysis, the ionic compound of potassium and oxygen with the empirical formula KO is potassium peroxide (K2O2).