  We study the effect of nuclear reaction on a thin, axisymmetric,
differentially rotating, inviscid, steady accretion flow around a black hole
from an analytical point of view. We find that for most of the reasonable disk
parameters, when $p-p$-reaction, dissociation of deuterium and helium are taken
into account, the transonic region of the disk continues to have the inner
sonic point and if the temperature of the flow at the injection sonic point
could be raised (by say, some heating processes) the flow would to pass through
this inner sonic point. Otherwise, the flow may be unstable. We use the sonic
point analysis to study the solution. In the rest of the disk parameters the
inner sonic point is absent altogether and the flow will definitely be
unstable.
