Buffon (George-Louis Leclerc, Comte de Buffon, 1707-1788), primary and secondary selections.[1] The Comte de Buffon was a contemporary of Linnaeus, and his great rival. From Buffon’s perspective, the Linnaean hierarchy suggested a common ancestry for all animals, and this Buffon found absurd. Buffon thus attributed evolutionary ideas to his opponent, even though Linnaeus (for the most part) flatly denied the possibility that species could change. Note that this selection includes original and secondary material. The Count of Buffon was […]
Abstract: The enthalpy of vaporization, entropy of vaporization at 298 degrees Kelvin, and the compressibility factor of Heptane were determined by measuring the vapor pressure of the liquid at varying temperatures. The enthalpy of vaporization was 26.77 ± 0.52 (kJ/mol). The entropy of vaporization at 298 K was 89.8 ± 1.7 (J/K mol). The compressibility factor was 1.31. The literature value for the enthalpy of vaporization was 35.07 (kJ/mol). The literature value for the entropy of vaporization at 298 K […]
Introduction The importance of being able to identify bacterial unknowns allows us to determine potential pathogenic microorganisms that can be harmful to humans. The identification of bacterial unknowns provides information to medical professionals to diagnose and properly treat patients with therapeutic strategies such as prescribing antibiotics to kill specific pathogenic microorganisms. Possible methods to identify bacterial unknowns include basic differential staining and biochemical tests. Gram staining allows identification of the morphology and cell wall structure of a bacterial unknown, which […]
AIM: The aim of this experiment is to carry out an addition reaction using trans-stilbene and bromine reagent to produce 1,2-dibromo-1,2-diphenylethane. As most chemicals used in this experiment are toxic / harmful, PPE must be used throughout and the experiment should be carried out inside a fume hood. THEORY: Bromine and chlorine readily undergo addition reactions with alkenes. This practical involves the bromination of trans-stilbene using a 10% bromine dichloromethane solution. Hence, an addition reaction takes place and 1,2-dibromo-1,2-diphenylethane is […]
Abstract Via acid/base titration with a primary standard (potassium hydrogen phthalate) an NaOH solution of unknown concentration was standardized. Once the NaOH solution was standardized, it was used as to determine the concentration of a KHP solution of unknown molarity. In both instances, an acid/base indicator was used to signal the endpoint. Using the recorded volumes from the titrations, the molarity of the known solutions, and the molar mass of the compounds in the solutions of known concentration, the […]
By: Jane Huang, Stephanie Thomas and Vasthi Yanes Chemical Reaction Equation Reaction Table Introduction The purpose of this lab is to perform a reduction of trans-cinnamaldehyde. This process consists of 1) mixing trans-cinnamaldehyde with sodium borohydride and methanol, 2) employing rota-vap and the rinsing and removal of aqueous layers to purify mixture, 3) drying the precipitate via gravity filtration. The use of metal hydrides, such as sodium borohydride and lithium aluminum hydride, is the most commonly used out of […]