Which of the following is the correct formula for an ionic compound formed between K^+ and O^{2-} ions?

• A. K_2O_2
• B. KO
• C. KO_2
• D. K_2O

Answer: (D)

Verified step by step guidance

1. Identify the charges of the ions involved: potassium ion (K^+) has a charge of +1, and oxide ion (O^{2-}) has a charge of -2.
2. Determine the ratio of ions needed to balance the total positive and negative charges so that the compound is electrically neutral.
3. Since each K^+ has a +1 charge and O^{2-} has a -2 charge, two K^+ ions are needed to balance one O^{2-} ion.
4. Write the formula by placing the number of each ion as subscripts: two potassium ions and one oxide ion gives the formula \(K_2O\).
5. Verify that the total positive charge (+2 from two K^+) balances the total negative charge (-2 from one O^{2-}), confirming the compound is neutral.