Spectroscopic and Optical Methods Flashcards
Define spectroscopy
absorption or emission spectrum
Define spectrophotometry
quantitative measurement of the absorption or emission
UV-Vis
Ultraviolet-Visible Spectrophotometry
FT-IR
Fourier-transform infrared sprectrophotometry
FAAS
Flame atomic absoption spectrophotometry
Refractometry
bending of light through media
Polarimetry
polarization (plane rotation) of light; for optically active compounds
Turbidimetry
scattering of light
Colorimetry
measurement of color variation
Common range of wavelength in UV-Vis
200 nm to 700 nm
Arrange in increasing wavelength
: Gamma, x, UV, visible, microwave, radio waves (FM, AM, long)
Main parts of spectrophotometer
Light source, monochromator, sample compartment, detector
Light source for UV and Visible
deuterium lamp for UV, tungsten lamp and gallium LED for visible
Sample compartment for UV and Visible
Quarts for UV, regular glass or polystyrene for visible
Subparts of monochromator
: entrance slit, dispersion device, exit slit
What is Beer-Lamber Law?
Relates concentration to absorbance: A = kbC = -log I/I0
T/F: Color absorbed is complementary to the color transmitted or reflected
: True
Concentration can be calculated from calibration curve if the ___ is known
absorbance
Calibration curve axes
y-axis: absorbance, x-axis: concentration
Calibration curve axes
y-axis: absorbance, x-axis: concentration
Calibration curve trend
Linear
Measurement must be made in the ___ for Beer’s law to apply
maximum absorption wavelength