CHEM 524 -- Course Outline (Part 12)—2009 For pdf of these notes, click here For HTML of 2005 notes with links, click here VIII. Atomic Spectroscopy (survey text: Chap. 7-11, book is very detailed, we will not do) A. General Purpose— determine trace amounts of metals in samples, most common a. Value: trace element sensitivity and selectivity i. -- depend on calibration ii. —no absolutes due to sampling variation b. Big issue: atomize—strip off all bonds and measure vaporized atoms but wish to determine solution concentration of source of atoms i. technique of atomization critical step – efficiency affect detectivity ii. Steps: solution nebulize desolvate atomize (ionize possible) – See Chap 7-1 iii. Each happens in a transient process (flame, arc, spark, furnace) iv. Goal to get absorbance or emission from stable sample reflecting input
11
Embed
CHEM 524 Course Outline (Part 12)—2009 For pdf of these ...ramsey1.chem.uic.edu/tak/chem52409/notes12/notes12_09.pdf · technique of atomization critical step – efficiency affect
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
CHEM 524 -- Course Outline (Part 12)—2009
For pdf of these notes, click here
For HTML of 2005 notes with links, click here
VIII. Atomic Spectroscopy (survey text: Chap. 7-11, book is very detailed, we will not do)
A. General Purpose— determine trace amounts of metals in samples, most common
a. Value: trace element sensitivity and selectivity
i. -- depend on calibration
ii. —no absolutes due to sampling variation
b. Big issue: atomize—strip off all bonds and measure vaporized atoms
but wish to determine solution concentration of source of atoms
i. technique of atomization critical step – efficiency affect detectivity
ii. Steps: solution nebulize desolvate atomize (ionize possible)
– See Chap 7-1
iii. Each happens in a transient process (flame, arc, spark, furnace)
iv. Goal to get absorbance or emission from stable sample reflecting input
v. Lots can go wrong, chemical interactions, burner orientation. . . —calibrate to avoid