Answer to Question #234267 in Chemical Engineering for Lucky

Question

b) Nitrous oxide decomposes according to the second order rate equation 2N₂0→2N₂ +0₂ The rate constant is 977 cm³/ (mol. s) at 895°C. Calculate the fraction decomposed at 1s, 10s, and at 10 min in a constant volume batch reactor. The initial pressure (all N₂O) is 1 atm.

Answer 1

The units of a rate constant will change depending upon the overall order. The units of rate are always M/s or Ms-1 To find the units of a rate constant for a particular rate law, simply divide the units of rate by the units of molarity in the concentration term of the rate law. 

The rate law for a chemical reaction is an equation that relates the reaction rate with the concentrations or partial pressures of the reactants. For the general reaction with no intermediate steps in its reaction mechanism, meaning that it is an elementary reaction, the rate law is given by: r =k[A]x[B]y