Ionic properties of calcium chloride

Steps:

• Calcium chloride (CaCl₂) forms from calcium (metal) and chlorine (non-metal), making it ionic.
• Ionic compounds in solid form consist of positive and negative ions arranged in a regular, giant lattice.
• High lattice energy leads to specific physical properties like high melting point and insolubility or solubility patterns.
• Compare options: only ionic lattice matches the structure.

Why C is correct:

• Ionic compounds like CaCl₂ have ions held by electrostatic forces in a three-dimensional lattice, as defined by ionic bonding theory.

Why the others are wrong:

• A: Ionic lattices require high energy to break, resulting in high melting point (around 772°C for CaCl₂).
• B: In solid form, ions are fixed in the lattice and cannot move to conduct electricity.
• D: CaCl₂ dissolves readily in water due to ion hydration.

Final answer: C