Origin of water vapor
Examples from the Web for water vapor
The total volume of air (which may be designated as V) includes the volumes of carbon dioxide, water-vapor, oxygen, and nitrogen.
The air entering the chamber is free from water-vapor and carbon dioxide.
The resulting products of this combustion, if it is complete, are carbon dioxide and water-vapor.Artificial Light|M. Luckiesh
As the water-vapor is absorbed by the sulphuric acid, there is a slight increase in volume of the acid.
Any variations in the residual amount of carbon dioxide or water-vapor likewise affect the oxygen.