which compound is a conjugate acid-base pair?
Report Abuse. 1  H3PO4. Within the BrÃ¸nstedâLowry acid-base theory (protonic), a conjugate acid is the acid member, HX, of a pair of two compounds that transform into each other by gain or loss of a proton (hydrogen ion). 2  http://www.kentchemistry.com/links/Acids...