Ionic compounds form between metals and non-metals

Steps:

• Ionic compounds typically consist of a metal cation and non-metal anion, forming a lattice structure.
• Identify the chemical formula for each option to check for metal-nonmetal pairs.
• Ammonia (NH₃) involves only non-metals, so covalent.
• Calcium chloride (CaCl₂) pairs metal calcium with non-metal chlorine, so ionic.
• Ethanoic acid (CH₃COOH) and hydrogen chloride (HCl) are molecular with covalent bonds.

Why B is correct:

• Calcium chloride (CaCl₂) is an ionic compound because it forms from the electrostatic attraction between Ca²⁺ cations and Cl⁻ anions, following the definition of ionic bonding between metals and non-metals.

Why the others are wrong:

• A: Ammonia (NH₃) is a covalent molecular compound with shared electrons between nitrogen and hydrogen.
• C: Ethanoic acid (CH₃COOH) is an organic acid with covalent bonds in its carbon chain and functional groups.
• D: Hydrogen chloride (HCl) is a diatomic molecular compound with a covalent bond between hydrogen and chlorine.

Final answer: B