Assign charges to the oxygen-containing anions in the following compounds: (a) CsO₂ (b) BaO₂

Verified step by step guidance

1. Identify the oxidation state of the metal in each compound. For cesium (Cs) in CsO₂, it is typically +1, and for barium (Ba) in BaO₂, it is typically +2.
2. Determine the overall charge of the compound. Since both CsO₂ and BaO₂ are neutral compounds, the sum of the oxidation states of all atoms must equal zero.
3. Assign the oxidation state to the oxygen atoms. In peroxides, such as BaO₂, each oxygen has an oxidation state of -1. In superoxides, such as CsO₂, each oxygen has an oxidation state of -1/2.
4. Calculate the total charge contributed by the oxygen atoms in each compound. Multiply the oxidation state of oxygen by the number of oxygen atoms present in the compound.
5. Ensure that the sum of the charges from the metal and the oxygen atoms equals zero to confirm the correct assignment of charges.

Key Concepts

Oxidation States

Oxidation states are a way to keep track of electrons in chemical compounds. They indicate the degree of oxidation of an atom in a molecule, helping to determine the charge of ions. In compounds, the sum of the oxidation states must equal the overall charge of the compound, which is crucial for assigning charges to anions.

Common Anions

Common anions are negatively charged ions that frequently occur in chemical compounds. For example, the peroxide ion (O₂²⁻) is a common anion that consists of two oxygen atoms bonded together, carrying a -2 charge. Recognizing these common anions is essential for determining the charges in compounds containing oxygen.

Ionic Compounds

Ionic compounds are formed from the electrostatic attraction between positively charged cations and negatively charged anions. The charges of the ions must balance to create a neutral compound. Understanding the nature of ionic bonding is key to assigning the correct charges to the anions in compounds like CsO₂ and BaO₂.