Competitive Nucleophiles By: Doug Kruse Abstract: The competitive nucleophilic reaction of two nucleophiles, chloride and bromide ion with tert-butyl alcohol have been studied in this experiment. Nucleophilic substitution at the tertiary carbon to form a haloalkane was observed. During nucleophilic substitution, a nucleophile replaces a leaving group from a carbon atom, using its lone pair electrons to form a new bond to the carbon atom.1 Nucleophilic substitution can occur through two pathways namely SN1 and SN2 reaction mechanism. The former […]
Thin Layer & Column Chromatography By: Lisa Mickey Introduction Thin layer chromatography (also known as TLC) is the physical separation of a mixture into its individual components by distributing the components between a stationary phase (the porous TLC plate) and a mobile phase (the solvent that moves through the stationary phase and carries the material that needs to be separated. The driving force to separate components is capillary action. This method can be […]
Distillation By: Tim Dimond Introduction/Purpose The purpose of this lab was to purify an unknown mixture of acetone/water by both fractional and simple distillation. This process is a viable method for separation of these two liquids because of the large separation in their boiling points. Material -Water and acetone mixture Equipment – A setup for fractional distillation and simple distillation -100 mL round bottom flask -Volume measuring equipment -Heating equipment Procedure Obtain 70 mL of the acetone/water solution in a […]
Activity Coefficients Experiment By: Stephen Fry Introduction While pH is often treated as the negative logarithm of the concentration of protons or hydronium ions, p[H], it is defined as the negative logarithm of the activity of hydrogen ions in a solution: pH = -log(aH+) = -log(cH+ ×γH+) Where c is the molal concentration and γ is the activity coefficient. However, the activity a single ion in solution cannot be measured due to the necessity of a counter ion. To overcome […]
Acid Impurity and Identification Through Molar Mass Calculation By Sena Contreras Introduction: The purpose of part I in the investigation was to determine if two methods of purifying succinic acid produce statistically similar results. We tested this using a pooled t-test; the null hypothesis being that there is no difference between the samples A and B. Sample A was purified by the first method, and sample B by the new method. The purity of each was found through an acid […]
Introduction The purpose of this experiment is to investigate the stereoselectivity of various reducing agents in the reduction of a carbonyl group. The first part of this experiment will focus on the stereoselectivity of sodium borohydride, lithium aluminum hydride, and lithium tri-sec-butylborohydride (L-selectride) in the reduction of 4-tert-butylcyclohexanone.1 The second part of this experiment will focus on the stereoselectivity of saccharomyces cerevisiae (baker’s yeast) in the reduction of ketone in ethyl acetoacetate.2 The stereoselectivity of each reducing agent will be […]
