Fluorescence Spectrophotometry of Riboflavin By: Andrew Tam Introduction This experiment was done to explore an aspect of spectroscopic analysis called fluorescence. This aspect involves shining an ultraviolet light, which will excite the electrons of certain molecules. When these excited electrons returned to their ground (original) state, energy is released and causes the molecule to emit light. This light can then be captured with the use of a detector to measure how intense the compound emits light as a result of […]
Determination of Salicylate via Reaction with Fe(III) By: Andrew Tam Introduction This experiment was performed to study aspects of spectroscopic analysis. To do so, we used an Ocean Optics spectrophotometer to collect optical absorbance spectra for different solutions. In doing so, we also aim to investigate the stoichiometry of reactions using the method of continuous variation. We did so by studying the absorbance of a salicylate complex. Salicylate and salicylic acid are common chemicals found in medications that are used […]
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 […]
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 […]
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 […]