Hypochlorous /(?)/

Hy·po·chlo·rous

Hypochlorous

a.
  1. Pertaining to, or derived from, chlorine having a valence lower than in chlorous compounds. (Chem.)

Phrases & Compounds
Hypochlorous acid
an acid derived from chlorine, not known in a pure state, but forming various salts, called hypochlorites.