Answer Key1-Final - AAS 1. AAS quantifies the amount of...

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

View Full Document Right Arrow Icon
AAS 1. AAS quantifies the amount of element present in a compound in a well separated gaseous vapor mixture by the amount of radiation absorbeb. The radiation absorption is proportional to the amount of specific element at specific wavelength. 2. cathode lamp – lens – sample – lens – monochromator – detector – amplifier – readout 3. Fe and Calcium - to analyze the amount of Fe in baby food - to make sure that we had enough calcium in our diet 4. sample must be ashed (wet ashed for Fe) or dry ashed (muffle furnace) and then dissolve in dilute acid 5. As the sample passes through the nebulizer, it burned the food into a fine mist, which then atomized at ~4500C flame with the fuel of nitrous oxide-acetylene. The hotter the flame, the higher rate of atomization and ionization. The radiation from the cathode lamp that was not absorbed goes through the monochromator, then converted to electric signal by the detector, amplified and recorded. 6. atomized and gaseous form 7. A=abc A= absorbance, a=molar absoptivity, b=flame length, c=concentration 8. 2 advantages : very sensitive (1ug/mL), intereferences can be easily corrected 2 dis.adv. : can only detect one kind of element each time, can not detect non- metal element Chromatography and TLC 1. a. chromatography is a technique to separate compounds in a mixture as they are carried by mobile phase through a stationary phase b. mobile phase is the moving material that is passed through the stationary phase c. stationary phase is the solid support or moiety that was absorbed to the solid support d. absorbent is the stationary phase in chromatography esp. adsorbent chromatography e. eluant is the the process removing the solute from the stationary phase 2. compound, mobile phase, stationary phase. 3. a. Absorption chromatography - polar liquid mobile phase - has bonded phase (the surface of the stationary phase is covalently bonded to organic group) - solid stationary phase b. Partition chromatography - liquid was absorbed to a solid support (silica gel) to form liquid stationary phase. Mobile phase is usually non polar, stationary
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.

This note was uploaded on 02/19/2008 for the course BIO 2900 taught by Professor Ghiorse during the Spring '07 term at Cornell University (Engineering School).

Page1 / 5

Answer Key1-Final - AAS 1. AAS quantifies the amount of...

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