Structure of Ionic Solids in Chemistry

Structure of Ionic Solids:

NaCl has an octahedral arrangement. Each Na+ ion is surrounded by 6 Cl- ions at the corner of a regular octahedron. Similarly, each Cl- ion is surrounded by 6 Na+ ions. In an ionic solid like NaCl, the repeating units are oppositely charged ions held together by a strong electrostatic force of attraction.

Number of atoms per unit cell for NaCl is 1/8 x 8 + 1/2 x 6 = 4

Ionic compounds, either in a motion state or in solution conduct electricity because the ions migrate towards the electrodes. In an ionic crystal, the ions are trapped in fixed places in the crystal lattice. Hence, they can’t migrate and therefore can’t conduct electricity. The boiling point and melting point of ionic compounds are higher than that of covalent compounds.