Use the References to access 1. Classify the compound Ba(OH)2 as ionic or covalent What is the name of this compound? 2. Classify the compound NO as ionic O covalent? What is the name of this compound? 3. Classify the compound phosphorus triiodide as ionic Or covalent What is the formula for this compound? 4. Classify the compound magnesium iodide as ionic or covalent What is the formula for this compound
The Correct Answer and Explanation is:
1. Ba(OH)₂
- Classification: Ionic
- Name: Barium hydroxide
2. NO
- Classification: Covalent
- Name: Nitric oxide
3. Phosphorus triiodide
- Classification: Covalent
- Formula: PI₃
4. Magnesium iodide
- Classification: Ionic
- Formula: MgI₂
Explanation
Compounds are classified as ionic or covalent based on the types of elements involved and the nature of the bonds. Ionic compounds form between metals and nonmetals, where electrons are transferred from one atom to another. Covalent compounds form between nonmetals, where atoms share electrons.
- Ba(OH)₂ (Barium hydroxide) is an ionic compound. Barium (Ba) is a metal from Group 2 (alkaline earth metals), and hydroxide (OH⁻) is a polyatomic ion composed of nonmetals. The bond between Ba²⁺ and OH⁻ is ionic. However, within the hydroxide ion, the bond between oxygen and hydrogen is covalent. The compound as a whole is classified as ionic because it consists of ions held together by electrostatic forces.
- NO (Nitric oxide) is a covalent compound because it is formed between two nonmetals: nitrogen and oxygen. These atoms share electrons rather than transferring them. It’s a simple diatomic molecule with a covalent bond and no metal element involved.
- Phosphorus triiodide (PI₃) is covalent as well. Both phosphorus and iodine are nonmetals. The compound forms through electron sharing, and the use of prefixes like “tri-” in the name indicates it is a molecular (covalent) compound. The formula PI₃ reflects one phosphorus atom and three iodine atoms.
- Magnesium iodide (MgI₂) is an ionic compound. Magnesium is a Group 2 metal and donates electrons to iodine, a halogen (nonmetal), which accepts electrons. This electron transfer forms Mg²⁺ and I⁻ ions, resulting in an ionic bond. The correct formula is MgI₂, showing one magnesium ion and two iodide ions to balance the charges.
Understanding these differences is key in predicting properties like melting points, conductivity, and solubility.
