Answer:
Binary Ionic Compound is formed when a single-element cation and a single-element anion combine.
Step-by-step explanation:
Binary compounds are those compounds which are made up of only two elements. When metal looses single electron it is changed to Cation and a non-metal on accepting one electron creates an Anion. Thus a Binary Ionic compound is formed by the cation and anion.
Example:
Sodium Chloride, NaCl: Made up of Na⁺ and Cl⁻
Potassium Iodide, KI: Made up of K⁺ and I⁻
Lithium Bromide, LiBr: Made up of Li⁺ and Br⁻