Quantitative Assay for Fluorescein By: David Gould In this experiment several concentrations and variations of fluorescein were created and measured spectrophotometrically to determine absorbance at a peak wavelength. A calibration curve was made from the external standards to ensure the data showed a trend, as well as get a rough idea of any concentrations from future absorbance readings. Once standard additions were prepared and a graph made from this data, a reliable concentration was also obtained using the x-intercept. Given […]
Transfer of Escherichia Coli By: Amudha Venugopalan, Sarah Councilor, and David Roehrich Introduction: Escherichia coli are prokaryotic bacteria that can be transformed by lateral gene transfer. E. coli are transformed by direct transfer which means the bacterial cell directly uptakes the DNA of the plasmid introduced to it (Wimpee et al. 2013). A plasmid is a circular small piece of self-replicating DNA, plasmids carry fewer genes therefore DNA can be passed between species of bacteria (Wimpee et al. 2013). The […]
The Synthesis and Gravimetric Analysis of Alum By: Omish Samaroo Introduction The purpose of this experiment is to synthesize the double salt alum, which has the formula KAl(SO4)2•nH2O, where n is the number of waters of crystallization that are incorporated into its crystalline structure. By determining the percent of water by mass in the compound through gravimetric analysis, the value of n in the empirical formula of alum can be determined. The presence of potassium, aluminum, and sulfate is determined […]
Ohm’s Law and Resistivity By: Alexis Huddleston Introduction: The purpose of this experiment was to gain an understanding of Ohm’s law, to experimentally evaluate the validity of the formulas used to determine equivalent resistance, and to find the resistivity of carbon. Ohm’s law, as stated in this activity, is defined as a fundamental rule for analyzing circuits which involve only one voltage, current and resistance in the simplest cases. Interestingly Ohm’s law is named for the relationship between […]
Electric Fields and Potentials By: Alexis Huddleston Introduction: The purpose of this experiment was to gain an understanding of electric fields and their potentials by using volts and point strategies. The electric potential as stated in this activity is created by the distribution of charges, which is a scalar quantity, determined by the different locations of voltage charges. Furthermore, potential charges are decreased when the points measured are farthest away from the equipotential base. Therefore, V is the electric […]
By: Ludmila Novikova Section A: Conductimetry and the Strength of Acids and Bases: Goal: To understand how conductivity experiments work and to be able to identify strong and weak acids and bases via the use of equilibrium constants. Summary: In this section of the lab, Dr. Thompson carried out several experiments to show how certain substances allow the conductivity of electricity to occur. 1.) The first experiment was one between sugars in water. There was a light bulb with a […]
