<Dd> F A 0 − F A + ∫ 0 V v d V = d N A d t (\ displaystyle F_ (\ mathrm (A) 0) - F_ (\ mathrm (A)) + \ int _ (0) ^ (V) v \, dV = (\ frac (dN_ (\ mathrm (A))) (dt))), </Dd> <P> where F is the inflow rate of A in molecules per second, F the outflow, and v is the instantaneous reaction rate of A (in number concentration rather than molar) in a given differential volume, integrated over the entire system volume V at a given moment . When applied to the closed system at constant volume considered previously, this equation reduces to: </P> <Dl> <Dd> r = d (A) d t (\ displaystyle r = (\ frac (d (A)) (dt))), </Dd> </Dl> <Dd> r = d (A) d t (\ displaystyle r = (\ frac (d (A)) (dt))), </Dd>

What is an equivalent expression for the rate of the reaction