Final Prep Answers

More documents

Recommendations

Info

Chem 155 <strong>Final</strong> review topics and questions: 2. Compare Ar-plasma and air-C 2 H 2 flames in the following categories: Quality circle correct Electron Ar-plasma has higher lower equal air-C 2 H 2 flame. density e - density than Temperature Ar-plasma is higher lower equal air-C 2 H 2 flame. temperature than Chemical Ar-plasma has higher lower equal air-C 2 H 2 flame. reactivity reactivity than Formation of Ar-plasma is higher lower equal air-C 2 H 2 flame. oxides likelihood than Atomization efficiency Ar-plasma is superior inferior equal to air-C 2 H 2 flame. 3. Compare inductively coupled plasma atomic emission spectrometry (ICP-AES) to flame atomic absorption spectroscopy (FAAS) in the following categories: Quality circle correct choice Cost to buy / ICP-AES is higher, lower, FAAS operate equal cost than Simultaneous ICP-AES is more, less, FAAS Multielement detection equally competent than Dynamic Range ICP-AES has larger, smaller, FAAS equal dynamic range than Detection Limit ICP-AES has higher, lower, equal detection limits than FAAS 4. Because of the mulit-element capability and atomization / temperature sensitivity of emission intensity, the following analytical method has proved highly successful in ICP-AES: a. Standard addidions c. D2 background correction b. Internal standards d. nonlinear calibration analysis 5. Formation of oxides or molecular species in flame/plasma can be suppressed by: c. EDTA or other complexing agents d. Addition of KCl to the matrix e. Addition of oxyanions such as sulfate or phosphate. f. Standard additions methods. 6. Ionization of analyte atoms in flame/plasma can be suppressed by: g. EDTA or other complexing agents h. Addition of KCl to the matrix i. Addition of oxyanions such as sulfate or phosphate. j. Internal standards methods.
Chem 155 <strong>Final</strong> review topics and questions: 7. Fill in the following table: Absorbance P Po %T C / M 0.00 1 1.00 100 0.0000 0.30 0.5 1.00 50 0.0003 1.00 0.1 1.00 10 0.001 2.00 0.01 1.00 1 0.002 3.00 0.001 1.00 0.1 0.003 A log %T 100 10 A %T 100 %T 100 10 A 100 10 0.3 50 100 10 1 10 100 10 2 1 100 10 3 0.1 %T 100 P P0 P %T 100 P0 8. Based on this, comment on the relative reliability (i.e. accuracy or precision) of absorbance measurements at A=1 and A=3. A=1 is good, A=3 means light power P is 1/1000 of blank - too small of a light power signal to work with
Page 1 and 2: Chem 155 Final review topics and qu
Page 11: Path of analyte through plasma or f

Final Prep Answers

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?