White arsenic is a toxic inorganic compound that has been used in various applications, including as a pesticide and a pigment. It is also known by several synonyms, including arsenic trioxide, arsenous oxide, arsenic(III) oxide, arsenolite, and arsenious acid. These terms are often used interchangeably, but they refer to the same substance that has a white crystalline appearance. Despite its many uses in the past, the use of white arsenic has been largely phased out due to its harmful effects on human health and the environment. Nonetheless, it remains an important subject of study and research for scientists and chemists.