Three researchers carry out a rates investigation on the substitution reaction of 2-chloro-2-methylpropane with nucleophile Y−(aq)\text{Y}^-\text{(aq)}Y−(aq) in the presence of a metal ion catalyst M2+(aq)\text{M}^{2+}\text{(aq)}M2+(aq).
(CH3)3CCl(aq)+Y−(aq)→M2+(aq)(CH3)3CY(aq)+Cl−(aq) \text{(CH}_3)_3\text{CCl(aq)} + \text{Y}^-\text{(aq)} \xrightarrow{\text{M}^{2+}\text{(aq)}} \text{(CH}_3)_3\text{CY(aq)} + \text{Cl}^-\text{(aq)} (CH3)3CCl(aq)+Y−(aq)M2+(aq)(CH3)3CY(aq)+Cl−(aq)Each researcher investigates the effect of changing the concentration of one of the species whilst keeping the other concentrations constant.
Their results are shown below.
| Experiment | [Y−(aq)]/mol dm−3[\text{Y}^-\text{(aq)}] / \text{mol dm}^{-3}[Y−(aq)]/mol dm−3 | [(CH3)3CCl(aq)]/mol dm−3[(\text{CH}_3)_3\text{CCl(aq)}] / \text{mol dm}^{-3}[(CH3)3CCl(aq)]/mol dm−3 | [M2+(aq)]/mol dm−3[\text{M}^{2+}\text{(aq)}] / \text{mol dm}^{-3}[M2+(aq)]/mol dm−3 | Initial rate /10−4 mol dm−3s−1 / 10^{-4} \text{ mol dm}^{-3} \text{s}^{-1}/10−4 mol dm−3s−1 |
|---|---|---|---|---|
| 1 | 0.05 | 0.80 | 0.15 | 2.40 |
| 2 | 0.05 | 0.80 | 0.45 | 7.20 |
Explain how the reaction orders can be determined from the researchers' results, and determine the rate equation and rate constant, including units.
