Electromagnetic Radiation and Concentration Curve Essay examples

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The purpose of this lab is to evaluate light absorption in a variety of solutions to identify an unknown solution’s concentration by using a spectrophotometer to measure a particular substances absorption of radiation at a precise wavelength in the visible region of the spectrum to construct a concentration curve. This was then compared to the peak of absorbance of the unknown to determine the concentration of the unknown substance (Kotz, 2014).
Spectroscopy is the study of light, which can be thought of as magnetic and electric waves or as photons, massless particles that travel as energy (Quantitative Spectroscopy: Theory and Practice, Brian C. Smith). To study light we often use a spectrophotometer is the contraption consisting of a white light source through a prism demonstrating refraction, which allows us focus individually on the multiple wavelengths emitted (Brian C. Smith). A= εlc or Beer’s Law states the relationship between the absorbance of a solution and the concentration of the absorbing analyte (Food Analysis, S. Suzanne Nielsen). The variable ε represents the molar absorptivity differs with the wavelength of light used in the measurement. A is the absorbance, c is the concentration and l represents the path length. Beer’s Law strictly applies to certain conditions, such as a homochromatic light source, dilute solutions and lastly a measurement of optimum wavelength also known as the absorbance peak (Haven, 1994). Absorption spectrum is defined as the absorbance of light at different wavelengths on a specific solution (Swamy, 2009). Due to the

Unknown Concentration

The objective of this lab was to find the concentration of iron in a solution with an unknown concentration. Through the use of the Beer-Lambert Law and spectrophotometry, one can find the absorbance of solutions with known concentrations of iron and create a calibration curve that can be used find the concentration of the unknown solution, which was calculated to being 10.5ppm Fe. This value is somewhat precise due to its relative standard deviation of 1.65%, and the errors were kept to a minimum…

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Essay on P4 Chem Lab Report

experiment, spectrophotometry was utilized as an essential tool. Spectrophotometry and UV-Visible radiation can be used in combination to determine concentrations of food dyes. Food dyes absorb electromagnetic radiation in the visible spectrum (Sandi-Urena et al). In this experiment, the interaction of UV-Visible radiation and organic molecules in commercial food products were studied to determine concentration of certain food dyes. From the given variety of dye colors, Red #40, Yellow #6, and Yellow #5…

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Nanalytical Chemistry Essay examples

3. Sampling- select a representative sample i. Replicate samples 1. homogenous Vs. Heterogeous 2. random heterogenous Vs. segregated Heterogenous a. random heterogenous= differences in concentration occur randomly and I a fine scale b. segregated heterogenous- large regions have obvious different compositions. Must make a composite smaple. (pull out same number as %) ii. Quantitative transfer- complete transfer…

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Importance Of Nuclear Chemistry

○ Matter (2) ○ Nuclear Reactions (41) ■ Stability ■ Radiation ■ Alpha ■ Beta ■ Gamma ○ Fission and Fusion (42) ■ Nuclear bombardment ■ Fission ■ Energy and “missing” Mass ■ Law of Conservation of Mass and Energy 2 ■ Einstein’s Famous Equation (E=mc ) ■ Nuclear Chain Reactions ■ Fusion ○ Applications of Nuclear Chemistry (43) ■ Radioisotope n ■ Halflife (A n=t / t t=A 0(.5) 1/2 ■ Biological Effects of Radiation Atomic structure ○ Theory (6) ○ Atoms (7) ○ Mass, moles…

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Ecology and Evolution Final Essay

Describe Griffith’s experiment that showed bacterial transformation: (How Gene’s work) (on slides from How Gene’s Work) He took two strains of Streptococcus (which causes pneumonia in mammals) and had 2 strains. R (harmless, nonpathogenic) and S (pathogenic). First, starts with injecting living S cells that have a protective capsule, the mouse dies because capsule protects the S strain from the mouse’s defenses. It is pathogenic. Then, injects living R cells with no protective capsule. Mouse…

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