Refer to the illustration below.

(i) Identify the sphere that depicts a metal atom and the sphere that depicts a nonmetal atom.

(ii) Among the products, identify the spheres that depict a cation and the sphere that depicts an anion.

List the following from largest to smallest size: Sb, Sb³⁺, Sb^3–.

The relative ionic sizes of Be²⁺, Na⁺, F^–, and S^2– are shown below. In between which ions would you place Mg²⁺ and O^2– ions?

Calculate the cation-ion distance for the following compounds: MgS, CaO, SrO. The ionic radii of some elements are given below:

Ion              Ionic Radius (pm)
Be²⁺            59
Mg²⁺           86
Ca²⁺           114
Sr²⁺            132
O^2–             126
S^2–             170
Se^2–           184
Te^2–           207

Arrange this isoelectronic series in order of increasing atomic radius: Se^2-, Sr²⁺, Rb⁺, Br^-.