University of Limpopo
Turfloop campus
Faculty of Sciences & Agriculture
School of Physical and Mineral Sciences
Department of Chemistry
SCHA032
Analytical Chemistry 3
Study Guidelines
2019
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ANALYTICAL CHEMISTRY MODULE
Prescribed Text book:
Skoog DA, West DM, Holler FJ and Crouch SR; Fundamentals of Analytical Chemistry,
9th edition, International Edition
Chemistry is the experimental and theoretical study of materials on their properties at both the
macroscopic and microscopic levels. Analytical Chemistry is a measurement science
consisting of a set of powerful ideas and methods that are useful in all fields of science,
engineering, and medicine.
In this inorganic chemistry module, we are planning to cover the topics as shown in Figure
below.
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1. SPECTROCHEMICAL METHODS
1.1. INTRODUCTION TO SPECTROCHEMICAL METHODS
Reference: Skoog et al.Fundamental of Analytical Chemistry, 9th ed, Chapter 24, page 648
After studying this topic student should be able to:
– Define each spectroscopic method
– Describe each spectroscopic method principles
– Explain major components of each spectroscopic method and their functions
– Explain application of each spectroscopic method
– Explain factors affecting function of each spectroscopic method
– Describe advantages & disadvantages of each spectroscopic method
The word spectroscopy implies that we will use the electromagnetic spectrum to gain
information about organic molecules. The modifier ultraviolet means that the information will
come from a specific region of the electromagnetic spectrum called the ultraviolet region. The
electromagnetic spectrum includes all radiation that travels at the speed of light c (3 x 1010
cm/sec). The electromagnetic spectrum includes radio waves, which have long wavelengths,
x-rays, which have short wavelengths, and visible light, which has wavelengths between those
of radio waves and x-rays. All of these waves travel at the speed of light. We normally describe
these waves in terms of their energy. Of the three kinds mentioned, x-rays are most energetic,
visible light next, and radio waves least energetic. Thus, the shorter the wavelength, the greater
the energy of an electromagnetic wave.
Electromagnetic radiation (EMR, Figure below) has a dual nature; it has the characteristics of
both waves and particles. These particles are so tiny that they are indistinguishable from a
wave.
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Both forms of EMR are important. From the wave nature of the waves we get the wavelength
() or distance between two crests. The wavelength is related to the frequency (), how many
wavelengths pass a given point in a given time, by the velocity of the wave c. From the
particulate nature of EMR, we get the energy E of a given wave, which is proportional to its
frequency. Plank’s constant h turns the proportionality into an equation. The mathematical
relationships among these variables are shown below.
Frequency and Wavelength: = c/ or = c/ or c =
Energy and Frequency: E or E = h
Energy and Wavelength: E = hc/
Visible light includes the rainbow colors red, orange, yellow, green, blue, indigo, and violet.
A handy acronym for these colors is ROYGBIV, said like the name of a person called Roy.
Note red is at the low-energy end of the visible spectrum and violet is at the high-energy end.
These facts allow us to quickly understand the terms infrared and ultraviolet. The prefix infra
means below, and the prefix ultra means above. Thus, infrared radiation is outside the visible
range and lies just below red on the energy scale. That is, infrared radiation is less energetic