This is always the case in a decomposition reaction. Don't forget that!! Figuring out what the products are in decomposition is harder (maybe you'll think it's easier!!) because you will have to recognize several categories of decomposition reactions.
Geology. a small, usually spherical cavity in a rock or mineral, formed by expansion of a gas or vapor before the enclosing body solidified. Origin of vesicle.
cyst. n. 1. An abnormal membranous sac in the body containing a gaseous, liquid, or semisolid substance. 2. A sac or vesicle in the body. 3. Biology A small capsulelike sac that encloses certain organisms in their dormant or larval stage. 4. Botany A thick-walled resting spore, as in certain algae or fungi.