Is rate of product always positive and rate of reactant always negative?
Solution,
Yes the rate of reactant is always negative as the concentration of a reactant always decreases with time, so it's taken negative. And concentration of products always increases with time so taken positive.
Yes the rate of reactant is always negative as the concentration of a reactant always decreases with time, so it's taken negative. And concentration of products always increases with time so taken positive.