Write formulas for each of the following compounds:(a) Sodium peroxide(b) Aluminum bromide (c) Chromium(III) sulfate

Verified step by step guidance

1. Identify the ions involved in each compound and their charges.
2. For sodium peroxide, recognize that sodium (Na) has a +1 charge and peroxide (O2) has a -2 charge.
3. For aluminum bromide, recognize that aluminum (Al) has a +3 charge and bromide (Br) has a -1 charge.
4. For chromium(III) sulfate, recognize that chromium(III) (Cr) has a +3 charge and sulfate (SO4) has a -2 charge.
5. Combine the ions in each compound to balance the overall charge, ensuring the total positive charge equals the total negative charge.

Key Concepts

Ionic Compounds

Ionic compounds are formed when metals transfer electrons to nonmetals, resulting in the formation of positively and negatively charged ions. The electrostatic attraction between these oppositely charged ions holds the compound together. Understanding the charges of common ions is essential for writing correct formulas for ionic compounds.

Polyatomic Ions

Polyatomic ions are ions composed of two or more atoms that are covalently bonded together and carry a net charge. Examples include sulfate (SO4^2-) and peroxide (O2^2-). Recognizing these ions is crucial when writing formulas for compounds that contain them, as they often appear in the names of the compounds.

Nomenclature Rules

Nomenclature rules provide a systematic way to name chemical compounds and derive their formulas. For ionic compounds, the name typically reflects the cation followed by the anion, with specific rules for transition metals and polyatomic ions. Familiarity with these rules is necessary to accurately translate compound names into their corresponding chemical formulas.