👉 Arsenous is a chemical compound that has been used historically in various contexts, including medicine and nutrition. It is composed of three elements: arsenic (As), oxygen (O2), and hydrogen (H). The compound name "arsenic" comes from the Latin word "arsenum," which means "black." In its pure state, arsenic has a reddish color and a bitter taste. However, when it is dissolved in water or other substances, it turns dark brown