Lab # 4 - Lab 4 Kinetics Of Nucleophilic Substitutions Name...

Info iconThis preview shows pages 1–5. Sign up to view the full content.

View Full Document Right Arrow Icon
Lab # 4 Kinetics Of Nucleophilic Substitutions Name: Partner’s Name: Date:
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Introduction/Objective : The purpose of this experiment is to observe the kinetics of a reaction. The reaction that is taking place is an SN1 mechanism. The kinetics of hydrolysis of t-butyl chloride will be examined, by varying the temperature, solvent polarity, concentrations of hydroxide and t-butyl chloride and the structure of the substrate. Figure 1: The SN1 Mechanism In The Hydrolysis Of t-butyl Chloride Step 1: The Formation Of a Carbocation (Rate-Determining Step) CH 3 CH 3 CH 3 C Cl CH 3 C+ + Cl - CH 3 CH 3 Step 2: Addition Of Water CH 3 H 2 O CH 3 C+ ( CH 3 ) 3 C OH + H Cl CH 3 Procedure/Observations : The procedure that was followed came from the York Summer Organic Lab Manual. However when conducting the study of solvent polarity, we designed our won procedure. To attain the water acetone ration of 60:40, 4ml of t-butyl chloride was placed in a flask. Then 5.6ml of distilled water was mixed with 0.4ml of sodium hydroxide in to another flask. Then the rest of the procedure was followed from the general procedure. When doing these studies, one must know when the reaction is 10% complete or 20% complete. The initial blue color to the yellow color indicated that the reaction took place and was 10% or 20%, depending on the experiment, completed.
Background image of page 2
Experimental Results : Table 1: Variation of Hydroxide Concentration Run Completion (%) Time (sec) K (sec -1 ) [t-Butyl Chloride] (mol/L) [Sodium Hydroxide] (mol/L) Reaction Rate (M sec -1 ) 1 10 65 1.62 × 10 -3 0.03 0.003 4.86 × 10 -5 2 20 130 1.72 × 10 -3 0.03 0.006 5.16 × 10 -5 3 30 260 1.37 × 10 -3 0.03 0.009 4.11 × 10 -5 Figure 2: Reaction Rates At Various Hydroxide Concentrations Reaction Rates At Various Hydroxide Concentrations 0 2 4 6 8 10 0 0.001 0.002 0.003 0.004 0.005 0.006 0.007 0.008 0.009 0.01 Concentration Of Hydroxide (mol/L) Reaction Rate (10 sec ) For Run 1: Concentration of Hydroxide in stock = 0.1M Volume of Hydroxide used = 0.0003 L Concentration Of t-Butyl Chloride in stock = 0.1M Volume of t-Butyl chloride used = 0.003L Total Volume = 0.01L [Hydroxide] = solution of Volume Total hydroxide of volume ] [hydroxide ×
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
0.01L 0003 . 0 0.1M L × = 0.003M [t-butyl Chloride] = solution of Volume Total chloride butyl - t of volume chloride] butyl - [t × [t-butyl chloride] = 0.01L 003 . 0 0.1 L × = 0.03M Calculating K For Run 1: t = 65 sec % reaction = 10 kt = 2.303 log - 100 / % 1 1 reaction k 65 × = 2.303 log - 100 / 10 1 1 k = 1.62 × 10 -3 (sec -1 ) Calculating Reaction Rates For Run 1: Rate = k [t-butyl chloride] Rate = (1.62 × 10 -3 ) × 0.03M Rate = 4.86 × 10 -5 M sec -1 Table 2: Variation of t-butyl Chloride Concentration Run [t-butyl Chloride] in Stock (mol/L) [t-butyl Chloride] in Reaction (mol/ L)) Time (sec) K (sec -1 ) Reaction Rate (M sec -1 ) 1 0.2 0.06 35 1.47 × 10 -2 8.82 × 10 -4 Table 1,
Background image of page 4
Image of page 5
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 06/06/2011 for the course CHEM 2020 taught by Professor Potvin during the Spring '09 term at York University.

Page1 / 15

Lab # 4 - Lab 4 Kinetics Of Nucleophilic Substitutions Name...

This preview shows document pages 1 - 5. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online