The degree of dissociation ((α)) of a weak electrolyte, ( AₓBy ), is related to the vant't Hoff factor (( i )) by the expression:
a) ( α= (i-1)/(x+y-1) )
b) ( α= (i-1)/(x+y+1))
c) ( α= (x+y-1)/(i-1) )
d) ( α= (x+y+1)/(i-1))