Which electron-dot formula best represents a compound that contains both ionic and covalent bonds?

• A. NaF
• B. Na[OCl]
• C. CO2
• D. HCl

Answer: (B)

Verified step by step guidance

1. Step 1: Understand the types of bonds in the given compounds. Ionic bonds form between metals and nonmetals where electrons are transferred, while covalent bonds form between nonmetals where electrons are shared.
2. Step 2: Analyze each compound: NaF consists of sodium (a metal) and fluorine (a nonmetal), so it is ionic; CO2 consists of carbon and oxygen (both nonmetals), so it is covalent; HCl consists of hydrogen and chlorine (both nonmetals), so it is covalent.
3. Step 3: Consider Na[OCl], which contains sodium (a metal) and the polyatomic ion hypochlorite (OCl⁻). The bond between Na⁺ and OCl⁻ is ionic, while the bond between oxygen and chlorine within OCl⁻ is covalent.
4. Step 4: Recognize that the compound Na[OCl] contains both ionic bonds (between Na⁺ and OCl⁻) and covalent bonds (within the OCl⁻ ion), making it the correct choice for a compound with both bond types.
5. Step 5: To represent Na[OCl] with an electron-dot formula, show the ionic bond by placing Na⁺ outside the brackets and the covalent bonds inside the brackets with shared electron pairs between O and Cl.