P1011
Solvent identity is known to affect the rates of certain chemical reactions. An experiment was conducted to investigate this effect on the rate of a first-order solvolysis reaction where a chloride ion is the leaving group. Tert-butyl chloride (TBC) was added to three solvents solutions: methanol, ethanol, and acetone, all in equal proportions with water. A small amount of sodium hydroxide was added to each solution in addition to phenolphthalein, an indicator that changes from pink to colorless as the solution becomes acidic.
(CH3)3CCl + X (CH3)3COR + HCl
X = (CH3OH, CH3CH2OH, CH3C(O)CH3)
The amount of time each solution took to become colorless was recorded in the table below.
| Solvent (1:1 H2O) | Time (mins) |
| Methanol | 1 |
| Ethanol | 5 |
| Acetone | 15 |
In a second set of experiments, the concentrations of tert-butyl chloride and propanol were varied to examine how they affected the reaction rate.
| Trial | [TBC] | [Propanol] | Initial rate (mol/sec) |
| 1 | 1.00 × 10-3 | 0.1 | 1.25 × 10-3 |
| 2 | 1.00 × 10-2 | 0.1 | 1.25 × 10-2 |
| 3 | 1.00 × 10-3 | 0.2 | 2.50 × 10-3 |
| 4 | 2.00 × 10-2 | 0.2 | 5.00 × 10-2 |
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