Theory: Atomic Absorption (AA) Spectroscopy is a quantitative analysis technique that uses the absorption of light through a flame and gaseous chemicals. AA Spectroscopy can be used for a multitude of purposes, most notably finding the concentration of one or a few elements in a compound. AA Spectroscopy can work in two different ways using an open flame and gaseous chemicals or a graphite furnace. Flame AA Spectroscopy works by taking a compound or element and disassociating it into an aqueous solution. The solution is then blown through an incredibly small nozzle which nebulizes the liquid into a very fine mist. The nebulized liquid is then blown through a flame with a very small beam of light passing through it. This light beam detects different elements in the flame and uses the known light absorbance of the element to determine the concentration of the element in the solution. The other form of AA Spectroscopy uses a graphite furnace to heat up and incinerate a sample. A solid compound is placed in the furnace which then heats up to 2000-3000 C effectively atomizing the compound and in the process turning the rest into ash. The light beam is then shot through the furnace as the solid is being heated and subsequently atomized and the machine records the absorbance rate much like the Flame AA Spectroscopy would. The difference between flame and furnace spectroscopy is in the atomization of the sample; because the Flame Spectroscopy uses pressure to atomize the compound, much of the compound is lost when sprayed …show more content…
This specific lab will focus on the two main variants of Atomic Absorption Spectroscopy: flame AA spectroscopy, and spectroscopy using a graphite furnace. The lab will also introduce and teach how to deal with both systematic and random error when using Atomic Absorption Spectroscopy.
Absorbance was defined as: log I_o/I where I_o is incident light and I is the transmitted light. Fluorescence emission spectrum is different from fluorescence excitation spectrum because it records different wavelengths of chemical s...
The color that was chose to be shined through the sample was purple. The spectrophotometer was set at a wavelength of 400nm to represent the purple color. It was zeroed using the blank meaning the spectrophotometer read zero as absorbance amount. The blank consisted of 5mL of water and 2.5 mL AVM and it was placed in cuvette. A solution with a known concentration of 2.0x10-4 M was used in the spectrometer.
The nano-thermal analysis method is capable of studying the specific regions of a sample irrespective of its composition. In a multi-component sample, the analysis methods make it possible for the researchers to distinguish between the different components and identify the different characteristics found in each of the sample (Craig, 2002). During the analysis of any sample, the nano-thermal method does not necessarily require the physical alteration of the sample. In its place, it is capable of analyzing any sample through surface studies.
We thank the University of Oklahoma and the chemistry faculty for providing the space, instructions, and equipment for the development of this report and experiment.
The task of interpreting William T. Vollmann’s works seems as monumental for the reader as writing the story oneself. The text of “The Visible Spectrum”, in fact, does not feature any extensively challenging vocabulary or particularly thwarting subject matter; yet it would seem that in all of its “objectivity” and “transparency”, there lies no obvious, dominant or intended interpretation. The narrative is ambiguous in its “message” to an infinite degree, and thus the reader must construct its “meaning” given only scraps of discontinuous plot, description and dialogue.
My interest into becoming an optometrist had begun when I was in high school; it happened in an unconventional way. It was not through watching videos, or someone explaining to me what optometry was, but rather, seeing the power of it firsthand. There was a point in my life where I felt emotions that I was unable to comprehend at the time. Seeing a family member on an operating table was the most petrifying moment that I have gone through, especially when the person on the table was my father. My father had to get a chalazion removed from his right eyelid. The doctor told my family that my father would be susceptible to certain health risks because of his diabetes and the severity of his cyst. This procedure was the hardest thing I have had to deal with in my life because it made me feel helpless. Usually, when my dad needs help he always asks me, but this time I could not do anything. It is interesting to think that something so small had such a big affect on my life.
The infrared spectrum yields direct information about the presence or absence of key functional groups. “The region of the infrared spectrum which is of greatest interest to organic chemists is the wavelength range 2.5 to 15 micrometers which correspond to approximately 4000 to 600cm-1”(Young). “When atoms or molecules absorb light, the incoming energy excites a quantized structure to a higher energy level. The type of excitation depends on the wavelength of the light. Electrons are promoted to higher orbirtals by ultraviolet or visible light, vibrations are excited by infrared light, and rotations are excited by microwaves” (Tissue).
Frey, Regina F., and Maureen J. Donlin. "Chemistry 257." Olfaction Tutorial. Washington University, 1998. Web. 4 Dec. 2013.
Thickett, Geoffrey. Chemistry 2: HSC course. N/A ed. Vol. 1. Milton: John Wiley & Sons Australia, 2006. 94-108. 1 vols. Print.
In addition, this investigation indicated that a flame test can be good way of distinguishing between different solutions, depending on the person performing the experiment. The colour changed to a crimson colour when the strontium nitrate solution was sprayed at the blue Bunsen burner flame. Similarly, all the other five solutions produced a colour when they were sprayed at the flame. However, each solution created a different and distinct colour and so the colours of the different elements were observed when placed in a Bunsen burner flame. Furthermore, this investigation indicated that a flame test can be good way of distinguishing between different solutions, depending on the person performing the experiment. Different atoms produce different colours and this effect can be used to distinguish between different elements. This is why a flame test can be used to tell the difference between certain solutions. However, almost everybody sees and describes colours differently. For instance, at first my partner and I both thought potassium nitrate and sodium nitrate produced the same colour, however, we were later able to see the difference. Therefore, a flame test can be good way of distinguishing between different solutions when the person who is experimenting sees the colours as distinctly
Optics Student Panel -Professional Development Activities During the student panel discussion held by the optics department, students (undergraduate, graduate and current professor) reflected on their experiences while here at the institute. The panel was conducted so that students could ask about graduate school, internships, and professional development within the optics major. Something special about the optics department is how they have Industrial Association, which is when members, faculty, and students connect with optics companies. With this opportunity, many panelists were able to receive jobs and addressed how they got hired, their internship/job experiences, and insight on what they did in their specific jobs.
The plasma consists of electronically excited atoms and ions, which can then be analyzed by the spectrometer. When the laser pulse terminates, the plasma begins to cool [11]. It is during this cooling process, where the electrons of the atoms and ions at the excited states decay back into their natural ground states, causing the plasma to emit characteristic wavelengths of light. The atomic emissions can be detected approximately 1 μs after the initial pulse. The emitted light from the plasma is collected by the spectrometer coupled with either a CCD or ICCD spectrograph detector module for the LIBS spectral analysis [11]. Each element correlates to a unique LIBS spectral peaks. Thus, by identifying the different peaks of the analyzed sample, its chemical composition can be rapidly
An oscilloscope is an electronic test instrument that is used to observe an electronic signal, typically voltage, as a function of time. In other words, it is a voltage versus time plotter. Oscilloscopes come in two basic types, analogue or digital, and support various features and functions useful for measuring and testing electronic circuits. An oscilloscope is a key piece of test equipment for any electronics designer.
Scattering takes place when obstacle dimension is smaller than wavelength of signal.Light scattering is a form of scattering in which light is the form of propagating energy which
Technology in the last few decades has impacted our understanding of biological entities greatly, the genome project being a prime example. The progress that biology sees follows closely with the development of new technology. It is very important to understand and visualise the composition and structures of biological materials or samples in order to extend and correlate this to the principles of life. Microscopy is a by far the most used and the most relevant technique in this regard. However the short comings in the technological aspect of this greatly limit the usage of this to comprehend the specifics.