Spectrophotometry Research Paper

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Spectrophotometry is actually defined as the quantitative computation of the transmission and reflection of properties of a material in terms of the wavelength [1] and it involves the use of a spectrophotometer. A spectrophotometer is a standard research tool that can be utilized in various fields worldwide and it is basically consists of a spectrometer and a photometer that can produce and determine monochromatic light transmitted or absorbed by a liquid sample in order to identify the material. Furthermore, the bandwidth of the spectrum and the measurement of linear range of absorption or reflectance are also stated as per important features of spectrophotometer. [2] The spectrophotometer was invented by Arnold J. Beckman and his colleagues …show more content…

It is a useful and applicable for determining the concentration and the absorbance of an unknown sample. The equation of Beer’s Law can be shown as follow:
Beer’s law: A = k • C A=Absorbance of the sample k = constant C= concentration of the sample As far as the equation is concerned, the absorbance of the sample is directly proportional to the concentration of the sample. This means that the more concentrated the solution of the sample is, the greater the absorption by the sample will be. The k value is dependent on the wavelength of the light used, the nature of the solvent and the travelling distance of the light. Since the value for K is always varying, therefore, it will be kept in constant to ease the burden of measuring the concentration sample. However, the absorbance of the solution cannot be measured directly. Therefore, transmittance is introduced into equation.
A = log (1/T) = -log (T)
A=Absorbance of the sample
T= Transmittance of the …show more content…

It can be positive or negative for the orders of diffraction depending entirely on the selected sign convention. From the equation above, the greater the discrete wavelength of the diffracted light, the maximum the diffracted light will have at angle of diffraction. Figure 7: Geometry of diffraction grating
As for the non-normal incidence case, if a plane wave is incident at any arbitrary angle, and the beam of light strikes the grating at angle of θ1 relative to the angle of θ, the grating equation will be shown as follow d(sinθ1+sinθ)=mλ This equation is applied independently of the surface refraction index.
As for lens, a lens is treated as an optical instrument to converge and diverge the light beams from the light source. There are two lenses, namely the concave lens and the convex lens. First of all, the main purpose of using convex lens is to converge the light rays at one point called the principle focus. The distance between the principal focus and the center of the lens is called the focal length. The end result is to obtain real, magnified and inverted

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