Question

The following data were obtained in a kinetic run from the decomposition of gaseous dinitrogen pentoxide at a set temperature.

2N₂O_5(g) = 4NO_2(g) + O_2(g)

Time (s)	0	100	200	300	400	500	600	700
[N2O5]	0.0200	0.0169	0.0142	0.0120	0.0101	0.0086	0.0072	0.0061

a.Graphically determine the order of the reaction.

b.Calculate the rate constant for the reaction.

c.Calculate the concentration of dinitrogen pentoxide in the reaction vessel after 350 seconds.

Answer 1

Ans. #a. The order of reaction with respect to [N₂O₅] is 1^st order because ln[N₂O₅] vs time gives a straight line (R² = 0.9999, closest to 1). A graph with its R² value closest to 1 exhibits maximum linearity.

#b. For first order kinetics rate, r = - k [A]

            Where, k = rate constant = - (slope of graph) = 0.0017 s^-1

#c.