Which of the following best describes the three–dimensional arrangement of ions in crystalline NaCl(s)?
a) Each Na⁺ ion is tetrahedrally surrounded by 4 Cl⁻ ions, and each Cl⁻ ion is likewise surrounded by 4 Na⁺ ions in a 1 : 1 ratio.
b) The solid consists of discrete NaCl molecules packed without long-range order.
c) Each Na+ ion is octahedrally surrounded by 6 Cl− ions, and each Cl− ion is likewise surrounded by 6 Na+ ions in a 1:1 ratio.
d) Each Na⁺ ion is cubically surrounded by 8 Cl⁻ ions, and each Cl⁻ ion is likewise surrounded by 8 Na⁺ ions.