Question

You will need to generate a set of graphs to answer this question. Concentration vs time data for the following decomposition reaction was collected at 300 K. The data is shown in the table below. What is the rate constant for the reaction at this temperature (in units of min-1)? H2O2(aq) → H2O(l) + 1/2 O2(g) time (min) [H2O2](mol/L) 0 0.00915 500 0.00486 1000 0.00256 1500 0.00136 2000 0.00072

Answer 1

Since the question itself presented in units for rate constant and as per units of rate constant min^-1

the reaction is of first order reaction.

So employ first order integral rate equation and calculate the rate constant for all data.

Initial concentration of H₂O₂ = 0.00915 mol/lit

The above method of substitution in first order integral equation confirms the given reaction is first order since the rate constants calculated at different time intervals remains the same .

The average is taken and k = 0.001270 min^-1

= 1.27 x 10^-3min^-1