Discussion
Home ‣ Biochemistry ‣ Chromatography Comments
- Question
Ion exchange chromatography is based on the
Options- A. electrostatic attraction
- B. electrical mobility of ionic species
- C. adsorption chromatography
- D. partition chromatography
- Correct Answer
- electrostatic attraction
- 1. In gas chromatography, the basis for separation of the components of the volatile material is the difference in
Options- A. partition coefficients
- B. conductivity
- C. molecular weight
- D. molarity Discuss
- 2. Internal conversion is where
Options- A. the spin of an excited electron reverses, changing the state of the molecule (from singlet state to triplet state or vice versa)
- B. A molecule converts its excess energy to light, and emits a photon
- C. A molecule converts excess electronic energy to vibrational energy
- D. none of the above Discuss
- 3. Fluorescence occurs when
Options- A. a molecule returns to the electronic ground state from an excited triplet state by losing it's excess energy as a photon
- B. a molecule returns to the electronic ground state from an excited singlet state by losing it's excess energy as a photon
- C. a molecule lowers its vibrational energy by losing it's excess energy as a photon
- D. none of the above Discuss
- 4. Why do fluorescence spectrometers often use double-beam optics?
Options- A. So a reference solution can be used
- B. To compensate for beam attenuation by the monochromator
- C. To compensate for power fluctuations in the radiation source
- D. All of the above Discuss
- 5. For a molecule to absorb IR, why must the molecule's vibrations cause fluctuations in the dipole moment of the molecule?
Options- A. Because a change in dipole moment lowers the energy required for electronic transitions
- B. Because for absorption to occur, the radiation must interact with the electric field caused by changing dipole moment
- C. Because fluctuations in the dipole moment allow the molecule to deform by bending and stretching
- D. All of the above Discuss
- 6. In reverse phase chromatography, the stationary phase is made
Options- A. non-polar
- B. polar
- C. either non-polar or polar
- D. none of these Discuss
- 7. The general expression for the appearance of a solute in an effluent is (where V is the elution volume of a substance , V0 void volume, kD distribution constant and Vi internal water volume)
Options- A. V = V0 + kDVi
- B. V = V0/Vi
- C. V = V0 - kDVi
- D. V/V0 = kDVi Discuss
- 8. Thin layer chromatography is
Options- A. partition chromatography
- B. electrical mobility of ionic species
- C. adsorption chromatography
- D. none of the above Discuss
- 9. A combination of paper chromatography and electrophoresis involves
Options- A. partition chromatography
- B. electrical mobility of the ionic species
- C. both (a) and (b)
- D. none of these Discuss
- 10. Which of the following statements is true for a refractive index detector in HPLC?
Options- A. It is more sensitive than a UV detector
- B. It can only be used for isocratic elutions
- C. It does not respond to many solutes
- D. none of above Discuss
Chromatography problems
Search Results
Correct Answer: partition coefficients
Correct Answer: A molecule converts excess electronic energy to vibrational energy
Correct Answer: a molecule returns to the electronic ground state from an excited singlet state by losing it's excess energy as a photon
Correct Answer: To compensate for power fluctuations in the radiation source
Correct Answer: Because for absorption to occur, the radiation must interact with the electric field caused by changing dipole moment
Correct Answer: non-polar
Correct Answer: V = V0 + kDVi
Correct Answer: adsorption chromatography
Correct Answer: both (a) and (b)
Correct Answer: It does not respond to many solutes
Comments
There are no comments.More in Biochemistry:
Programming
Copyright ©CuriousTab. All rights reserved.