Ch_322b_13.06

Ch_322b_13.06 - Chapter 13.6 lecture note

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

View Full Document Right Arrow Icon
The ultraviolet portion of the electromagnetic spectrum is approximately between 200-400 nm in wavelength. The visible region covers 400-800 nm. Absorption of radiation throughout the ultraviolet-visible region is associated with electronic transitions from filled to unfilled molecular orbitals. Ultraviolet-Visible Spectrophotometers The conventional spectrophotometer is based on the dual-beam principle. Radiation from a source lamp is split into two equal beams. source lamp I o I o One beam passes though a sample (usually in solution in a transparent cell). The other beam serves as a reference for determining the amount of radiation absorbed by the sample at each wavelength. reference sample I o I s monochromator (sorts wavelenths) I o ( ! ) I s ( ! ) photodetector I o ( ! ) and I s ( ! ) are compared The intensities of I o and I s are compared at a series of wavelengths. This information is displayed
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 / 6

Ch_322b_13.06 - Chapter 13.6 lecture note

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