Category : Natural Sciences

Identification of Unknown Sample 144a and 144b

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 an 1,2-dibromo-1,2-diphenylethane […]

Preparing Standard Acid and Base

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 […]

Reduction of trans-Cinnamaldehyde

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 […]

Calibrating Flow Meters and Exploring Reynolds Number Report

Introduction: Lab group three was asked to calibrate the rotameter and orifice meter. It was also requested of us to measure the range of Reynolds numbers able to be read in the CM3215 laboratory. The orifice meter is a section of pipe with a restriction that acts to create a pressure drop. As the fluid approaches the orifice, the pressure increases and then suddenly drops as a result of the velocity increase through the reduced cross sectional area. A rotameter […]

Titration of a Diprotic Acid: Identifying and Unknown Technical Memo

By: Vanessa Staats Introduction All pH vs. volume of NaOH graphs for each trial appeared as they should have and were used to determine equivalence points. The most clearly defined equivalence points were the second one for all three trials. Molecular weight was calculated, using only trials two and three, and unknown 2 was determined to be maleic acid. Trial one was thrown out when calculating the average molecular weight because the amount of NaOH in liters was vastly different than […]