A binary compound is a chemical compound composed of two different elements. Selenide, WATER, halide, OXIDE, and iodide are all examples of binary compounds. Selenide is an anion composed of selenium and another element, WATER is a compound of hydrogen and oxygen, halide is an anion composed of a halogen and another element, OXIDE is a compound of oxygen and another element, and iodide is an anion composed of iodine and another element.