Which of these are ionic compounds?
l B a O
l NH4CI
l KI
l NH3
l ІСІ
l SO2
The correct answer and explanation is :
Identifying Ionic Compounds
To determine which of the given substances are ionic compounds, we need to understand the nature of ionic bonding. Ionic compounds form when a metal transfers electrons to a non-metal, resulting in oppositely charged ions that attract each other. This generally occurs between elements with a large difference in electronegativity (such as metals and nonmetals).
Now, let’s analyze each compound:
- BaO (Barium Oxide) → Ionic
- Barium (Ba) is a metal, and Oxygen (O) is a nonmetal.
- Ba donates electrons to O, forming Ba²⁺ and O²⁻ ions.
- Since it consists of a metal and a nonmetal, BaO is ionic.
- NH₄Cl (Ammonium Chloride) → Ionic
- Contains NH₄⁺ (Ammonium ion, a polyatomic ion) and Cl⁻ (Chloride ion).
- Even though NH₄⁺ is a covalently bonded polyatomic ion, the bond between NH₄⁺ and Cl⁻ is ionic.
- Thus, NH₄Cl is ionic.
- KI (Potassium Iodide) → Ionic
- Potassium (K) is a metal, and Iodine (I) is a nonmetal.
- K donates an electron to I, forming K⁺ and I⁻ ions.
- KI is an ionic compound.
- NH₃ (Ammonia) → Covalent
- Composed of only nonmetals (Nitrogen and Hydrogen).
- Electrons are shared, not transferred.
- NH₃ is a covalent compound.
- ICl (Iodine Chloride) → Covalent
- Made of two nonmetals (Iodine and Chlorine).
- Electrons are shared rather than transferred.
- ICl is a covalent compound.
- SO₂ (Sulfur Dioxide) → Covalent
- Sulfur and Oxygen are both nonmetals.
- Electrons are shared, forming covalent bonds.
- SO₂ is covalent.
Final Answer:
✅ Ionic Compounds: BaO, NH₄Cl, KI
❌ Covalent Compounds: NH₃, ICl, SO₂
Ionic compounds generally have high melting and boiling points, conduct electricity when dissolved in water, and are solid at room temperature. Covalent compounds, on the other hand, can be gases, liquids, or solids and have lower melting points.