In the following drawings, red spheres represent cations, and blue spheres represent anions. Match the drawings (a)–(d) with the following ionic compounds: (i) Ca3(PO4) (ii) Li2CO32 (iii) FeCl2 (a) (iv) MgSO4 (a)
(b)
(c)
(d)

Verified step by step guidance

1. Identify the cations and anions in each compound: (i) Ca3(PO4)2, (ii) Li2CO3, (iii) FeCl2, (iv) MgSO4.
2. Determine the ratio of cations to anions in each compound: (i) 3:2, (ii) 2:1, (iii) 1:2, (iv) 1:1.
3. Analyze the images to identify the ratio of red spheres (cations) to blue spheres (anions) in each drawing.
4. Match the drawings to the compounds based on the cation to anion ratio observed in the images.
5. Verify the matches by ensuring the chemical formula corresponds to the visual representation of the ionic compound.

Key Concepts

Ionic Compounds

Ionic compounds are formed through the electrostatic attraction between cations (positively charged ions) and anions (negatively charged ions). They typically consist of a metal and a non-metal, where the metal donates electrons to become a cation, while the non-metal accepts electrons to become an anion. The resulting ionic bond creates a lattice structure, which is characteristic of solid ionic compounds.

Chemical Formula Representation

The chemical formula of an ionic compound indicates the ratio of cations to anions in the compound. For example, in Ca3(PO4)2, there are three calcium ions (Ca²⁺) for every two phosphate ions (PO₄³⁻). Understanding how to interpret these formulas is crucial for determining the correct arrangement of ions in the compound's structure, which is visually represented in the drawings.

Lattice Structure

The lattice structure of ionic compounds refers to the three-dimensional arrangement of ions in a repeating pattern. This structure maximizes the attractive forces between oppositely charged ions while minimizing repulsive forces between like charges. The stability and properties of ionic compounds, such as melting and boiling points, are largely influenced by the strength of these ionic interactions within the lattice.