Lab Report Chemistry

CHEM/ENCH 212

EXPERIMENT II: KINETICS OF NUCLEOPHILIC SUBSTITUTION

DATE OF SUBMISSION:
Table of Contents

Experimental

Table : Hazardous properties of chemicals used in the experiment.[1]
Acetone
Irritant. Do not inhale vapors. Highly flammable.
2 chloro, 2 methyl propane
Flammable.

Equipment
1. Conductivity probe
2. Constant temperature water circulation bath
3. Stir-plate with stirring magnets
4. 20 mL vials
5. Eppendorf pipette
6. Computer with LoggerPro

Procedure
For the fully detailed procedure, please refer to the CHEM/ENCH 212 Laboratory Manual.[2]

10 mL of a provided 85/15 water/acetone mixture was taken in a vial and
Original run, 10 mL of 85/15 acetone solution, 200 μL of 2-chloro, 2-methylpropane.
2. Same as original, but with 400 μL of t-butyl chloride.
3. Same as original but with 800 μL of t-butyl chloride.
4. Same as original but with 90/10 water acetone solution.
5. Same as original but with 80/20 water acetone solution.
6. Same as original, but with the water bath at
The activation energy obtained in Part C, 138.6 kJ/mol is not too far below the theoretical activation energy of 148.526 kJ/mol[6], while Part A confirms the theory that k is dependent on the initial concentration of reactants, since it is a first order reaction. This is clearly depicted in Figure 3, where the alteration of the amount of t-butyl chloride being added to the reaction vessel clearly produced a different rate constant. The findings from Part B of the experiment proved that the reaction followed the SN1 mechanism, with the increased concentration of water in the water/acetone mixture causing the reaction rate to increase due to the usage of polar solvents to stabilize the carbocation being produced during this mechanism in the slow, rate-determining step [5]. However, there were errors in the experiment, which led to the results being slightly off from theory, such as the lower than expected value for the activation