Cacodylic acid
（重定向自Dimethylarsenic acid）
![Structural formula](/Images/godic/202501/09/Cacodylic_acid.svg0958.png")
![Ball-and-stick model](/Images/godic/202501/09/Cacodylic-acid-3D-balls0958.png")
![](/Images/godic/202501/09/Cacodylic-acid-3D-sticks0958.png")
Cacodylic acid is the chemical compound with the formula (CH3)2AsO2H. Derivatives of cacodylic acid, cacodylates, were frequently used as herbicides. For example, "Agent Blue," one of the chemicals used during the Vietnam War, is a mixture of cacodylic acid and sodium cacodylate. Sodium cacodylate is frequently used as a buffering agent in the preparation and fixation of biological samples for electron microscopy.