For the given reaction: N2O5(g)→2NO2(g)+21O2(g)
The rate of the reaction is related to the rates of disappearance and formation of species as follows:
Rate=−dtd[N2O5]=21dtd[NO2]=1/21dtd[O2]=2dtd[O2]
Given the rate of disappearance of N2O5:
−dtd[N2O5]=6.25×10−3 mol L−1s−1
Rate of formation of NO2:
dtd[NO2]=2×(−dtd[N2O5])=2×6.25×10−3=12.5×10−3=1.25×10−2 mol L−1s−1
Rate of formation of O2:
dtd[O2]=21×(−dtd[N2O5])=21×6.25×10−3=3.125×10−3 mol L−1s−1