For the reaction: 2 N2O5 (g) → 4 NO2 (g) + O2 (g)

The experimental data for this reaction is :

t = 0.0 s [N2O5] = 0.80 M [NO2] = 0.0 M [O2] = 0.0 M

t = 20.0 s [N2O5] = 0.60 M [NO2] = 0.40 M [O2] = 0.10 M

What is the average rate of reaction during this time interval?

2 answers

avg rate = #M/time
That will be in M/s, right?
And I think you're playing pretty fast and loose with those = signs
The average rate of this reaction is -1/2[delta(N2O5)/delta t] = -1/2[(0.60M - 0.80M)/(20s-0s)] = -1/2(-.20/20) = -1/2(-0.01) = + 0.005 M/s