Concept explainers
(a)
Interpretation: While preparing a sample of UV-Vis analysis, if one assumes that the concentration of c, in methanol was 0.00600 g/L (True Value), against the actual value (Calculated Value) of 0.00576 g/L, the error in mg/L, in the mass of sample present in solutions needs to be determined.
Concept Introduction: The spectroscopy that uses light in the visible and adjacent range, giving absorption spectroscopy or reflectance spectroscopy, is termed as UV-Vis or Ultraviolet-Visible Spectroscopy.
(b) (i)
Interpretation: While preparing a sample of UV-Vis analysis, if one assumes that the concentration of c, in methanol was 0.00600 g/L (True Value), against the actual value (Calculated Value) of 0.00576 g/L, and assuming that a maximum was observed at a wavelength of 278 nm for this solution and that the value of A at this maximum was 0.623 when a 1-cm cell was used, and molar mass of 100 for
Concept Introduction: Depending on the chemical composition and structure of a chemical substance, light with a particular wave length is being absorbed by them, and a measure of such absorption of light, defining its strength is known by the term Molar Extinction Coefficient (
(b) (ii)
Interpretation: While preparing a sample of UV-Vis analysis, if one assumes that the concentration of c, in methanol was 0.00600 g/L (True Value), against the actual value (Calculated Value) of 0.00576 g/L, the information regarding the maximum value needs to be expressed.
Concept Introduction : When the value of molar extinction coefficient is known the value of log
(b) (iii)
Interpretation: While preparing a sample of UV-Vis analysis, if one assumes that the concentration of c, in methanol was 0.00600 g/L (True Value), against the actual value (Calculated Value) of 0.00576 g/L, the % error in
Concept Introduction: Molar concentration c can be derived by dividing the concentration of methanol by its molar mass
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Experimental Organic Chemistry: A Miniscale & Microscale Approach (Cengage Learning Laboratory Series for Organic Chemistry)
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