Analyzing the Reaction Order
To determine the order of the reaction, we can use the concentration data provided at various time intervals. The concentrations of the reactant are:
- At 1.0 hr: 0.1 mol/L
- At 2.0 hr: 0.08 mol/L
- At 3.0 hr: 0.067 mol/L
Calculating the Change in Concentration
- From 1.0 hr to 2.0 hr:
- Change = 0.1 - 0.08 = 0.02 mol/L
- From 2.0 hr to 3.0 hr:
- Change = 0.08 - 0.067 = 0.013 mol/L
Determining the Rate of Change
- Average rate from 1.0 hr to 2.0 hr:
- Rate = Change in concentration / Change in time = 0.02 / 1 = 0.02 mol/L/hr
- Average rate from 2.0 hr to 3.0 hr:
- Rate = Change in concentration / Change in time = 0.013 / 1 = 0.013 mol/L/hr
Order of Reaction Calculation
To find the order of the reaction, we can compare the rates of change with respect to the concentration.
If we assume a first-order reaction:
- The rate of reaction is proportional to the concentration of the reactant.
- A decrease in concentration will yield a corresponding decrease in the rate.
Since the rate decrease is not constant and appears to diminish over time, it suggests the reaction is not first-order.
Conclusion
The observed data indicates that the reaction follows a second-order kinetics:
- The rate decreases more significantly as the reaction progresses, suggesting that the reaction order is higher than one.
In summary, the reaction is likely a second-order reaction based on the concentration changes over time.