lab manual appendix b

lab manual appendix b - APPENDIX B Spectrometry When white...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
APPENDIX B Spectrometry When white light is allowed to pass through a prism, the light is diffracted into a spectrum of colors. This spectrum of colors has a range of wavelengths varying from 400 nm (violet) to 700 nm (red) and is referred to as the visible spectrum. Light of a single wavelength is called monochromatic light. When monochromatic light passes through solution samples of uniform thickness, part of the light is absorbed and part of the light is transmitted. M - monochromator I m - intensity of monochromatic light I t - intensity of transmitted light The quantity measured on the spectrometer is percent transmittance: T m t I I 100 Another quantity useful in spectrometry is the absorbance ( A ) of a solution: A log t m I I = log T % 100 Provided no changes occur in the species in solution, the relationship between absorbance and concentration is given by Beer's Law: A = kc Where c is the molar concentration of the solution and k is a proportionality constant such that k = ε b where = the molar absorption coefficient (constant for a particular species at a particular wavelength) and b is the length of the light
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 3

lab manual appendix b - APPENDIX B Spectrometry When white...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online