- an oxide containing five atoms of oxygen, as phosphorus pentoxide, P2O5.
Origin of pentoxide
1860–65; pent- + oxide
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for pentoxide
It is only known in solution; evaporation of the solution yields the pentoxide.
It burns readily in air, and is converted into the pentoxide when fused with acid potassium sulphate.
Columbium pentafluoride, CbF5, is obtained when the pentoxide is dissolved in hydrofluoric acid.
The oxyfluoride, CbOF3, results when a mixture of the pentoxide and fluorspar is heated in a current of hydrochloric acid.
It burns when heated in air, forming the pentoxide and sulphur dioxide.
- an oxide of an element with five atoms of oxygen per molecule
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012