Practical Report: Determination of Concentration Using a Standard Curve
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Practical report: Determination of concentration using a standard curve
Introduction Spectrophotometer is an instrument that confirms the measurement of specified wavelength of light that passes through medium. The measurement of light absorbance by a solution is also done with spectrophometer. Absorption spectrum Spectrometers are mainly and widely functional in identifying the components of solutions that helps determine the components’ concentrations. Compounds are experimentally identified differently through absorption characters. The absorbance of a solution at a certain wavelengths pertains to concentration of absorbing materials in the cell. The Lambert law explains and describes that the concentration of a solution can be determined by considering the relationship of absorbance and concentration. Aims or Objectives To have knowledge, experience and be most familiar with the use of spectrophometer To have knowledge and experience of tubes and other relevant laboratory facilities needed.
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To learn to independently prepare, conduct, and record laboratory practicals or demonstrations of many solutions of known concentration. To accurately measure the absorbance at its correct maximal wavelength at which it absorbs. To learn to plot a standard curve of absorbance and concentration To learn to determine the unknown solution concentration by considering or through standard curve Chemical Agents, Materials, and Methods The chemical agents written to procedurally follow were 1. 0.004 mM standard phenolphthalein 2. Unknown phenolphthalein solution 3. 0.12 M glycine-phosphate buffer, PH 11.2 I began this experiment by carefully ejecting eight tubes from their cupboard storages. I marked and arranged the tubes from one to eight. Next step was to fill up a beaker with de-ionized (distilled) water. In order to complete a protocol (table) in the prac booklet, I carefully used pipettes to add de-ionized water to tubes using the required measurements
Practical report: Determination of concentration using a standard curve
Introduction Spectrophotometer is an instrument that confirms the measurement of specified wavelength of light that passes through medium. The measurement of light absorbance by a solution is also done with spectrophometer. Absorption spectrum Spectrometers are mainly and widely functional in identifying the components of solutions that helps determine the components’ concentrations. Compounds are experimentally identified differently through absorption characters. The absorbance of a solution at a certain wavelengths pertains to concentration of absorbing materials in the cell. The Lambert law explains and describes that the concentration of a solution can be determined by considering the relationship of absorbance and concentration. Aims or Objectives To have knowledge, experience and be most familiar with the use of spectrophometer To have knowledge and experience of tubes and other relevant laboratory facilities needed.
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To learn to independently prepare, conduct, and record laboratory practicals or demonstrations of many solutions of known concentration. To accurately measure the absorbance at its correct maximal wavelength at which it absorbs. To learn to plot a standard curve of absorbance and concentration To learn to determine the unknown solution concentration by considering or through standard curve Chemical Agents, Materials, and Methods The chemical agents written to procedurally follow were 1. 0.004 mM standard phenolphthalein 2. Unknown phenolphthalein solution 3. 0.12 M glycine-phosphate buffer, PH 11.2 I began this experiment by carefully ejecting eight tubes from their cupboard storages. I marked and arranged the tubes from one to eight. Next step was to fill up a beaker with de-ionized (distilled) water. In order to complete a protocol (table) in the prac booklet, I carefully used pipettes to add de-ionized water to tubes using the required measurements
References: Department of Agriculture at Northern Melbourne Institute of Tafe, 2011, Living Systems I: Student Guide to Practical Classes, Northern Melbourne Institute of Tafe, Epping, VIC. (Pages 18-22) Note; I could not directly reference some of the descriptions in the introduction paragraph or anywhere in the report due to word limit issue. The general reference is cited above. 6