Three students investigate the kinetics of the acid-catalyzed chlorination of propanone in aqueous solution:
CH3COCH3(aq)+Cl2(aq)→H+(aq)CH3COCH2Cl(aq)+HCl(aq) \text{CH}_3\text{COCH}_3\text{(aq)} + \text{Cl}_2\text{(aq)} \xrightarrow{\text{H}^+\text{(aq)}} \text{CH}_3\text{COCH}_2\text{Cl(aq)} + \text{HCl(aq)} CH3COCH3(aq)+Cl2(aq)H+(aq)CH3COCH2Cl(aq)+HCl(aq)Each student investigates the effect of changing the concentration of one of the reactants whilst keeping the other concentrations constant.
Their results are shown below.
| Experiment | [Cl2(aq)]/mol dm−3[\text{Cl}_2\text{(aq)}] / \text{mol dm}^{-3}[Cl2(aq)]/mol dm−3 | [CH3COCH3(aq)]/mol dm−3[\text{CH}_3\text{COCH}_3\text{(aq)}] / \text{mol dm}^{-3}[CH3COCH3(aq)]/mol dm−3 | [H+(aq)]/mol dm−3[\text{H}^+\text{(aq)}] / \text{mol dm}^{-3}[H+(aq)]/mol dm−3 | Initial rate /10−5 mol dm−3s−1 / 10^{-5} \text{ mol dm}^{-3} \text{s}^{-1}/10−5 mol dm−3s−1 |
|---|---|---|---|---|
| 1 | 0.005 | 1.50 | 0.20 | 2.40 |
| 2 | 0.005 | 1.50 | 0.60 | 7.20 |
Explain how the reaction orders can be determined from the students' results, and determine the rate equation and rate constant, including units.
