11. Write the correct sequence for the set up of a HPLC system :
(a) Solvent reservoir
(d) Guard Column
(g) Analytical column
(1) (a), (f), (c), (g), (d), (b), (e)
(2) (c), (a), (f), (g), (d), (e), (b)
(3) (a), (c), (f), (g), (d), (e), (b)
(4) (a), (c), (f), (d), (g), (e), (b)
Answer: (4) (a), (c), (f), (d), (g), (e), (b)
12. Thermal Conductivity Detector in Gas-Chromatography consists of __________ identical filaments.
Answer: (2) Four
13. Assertion (A) : Derivatization prior to gas chromatography is often desirable.
Reason (R) : It improves the thermal stability of compounds, particularly those containing polar functional groups.
(1) (A) is correct, but (R) is wrong.
(2) Both (A) and (R) are correct.
(3) (A) is wrong, but (R) is correct.
(4) Both (A) and (R) are wrong.
Answer: (2) Both (A) and (R) are correct.
14. Dark current is associated with which of the following ?
(1) Photomultiplier tube
(2) Diffraction grating
(4) Band pass filter
Answer: (1) Photomultiplier tube
15. In FTIR spectrophotometer DTGS detector operates at __________.
(1) Ambient temperature
(2) Liquid Nitrogen temperature
(3) Liquid Oxygen temperature
(4) Liquid Hydrogen temperature
Answer: (1) Ambient temperature
16. In Neutron Activation Analysis, Crompton scattering results in which of the following ?
(1) Interference with the resulting signal
(2) Increase in peak intensity
(3) Increase in signal to noise ratio
(4) High resolution
Answer: (1) Interference with the resulting signal
17. In electrophoresis, with the increase in applied voltage there is also increase in flow of current.
The increase in flow of current results in :
(a) More generation of heat.
(b) Increase in buffer viscosity.
(c) Fast movement of ions.
(d) Works best with thermally instable compounds.
(1) (a) and (b) are correct.
(2) (b) and (d) are correct.
(3) (a) and (c) are correct.
(4) (a), (b) and (c) are correct.
Answer: (3) (a) and (c) are correct.
18. Performing electrophoresis on agarose gel where two electric fields are applied alternately at different angles for a defined time period, such an electrophoretic technique is known as :
(1) Pulsed-field gel electrophoresis
(2) Capillary electrophoresis
(3) Two dimensional gel electrophoresis
(4) Gradient gel electrophoresis
Answer: (1) Pulsed-field gel electrophoresis
19. Many forensic scientists keep a hand magnifier with them for preliminary examination of some exhibits, such as tattooing around a gun-shot hole in clothes. In connection with hand magnifier, which of the following statements is correct ?
(1) The object is within ‘F’ of the lens and it forms large virtual image.
(2) The object lies between ‘F’ and ‘2F’ and real image is formed at a distance greater than ‘2F’.
(3) The object is at ‘2F’ and the image is also formed at ‘2F’.
(4) The object is beyond ‘2F’ and the image is formed between ‘F’ and ‘2F’.
Where ‘F’ stands for focal length of the hand magnifier.
Answer: All of The Above
20. Polarising microscope has been used to study which of the following ?
(1) Density of soil particles
(2) Texture of soil particles
(3) Presence of humus in soil
(4) Presence of some minerals in soil
Answer: (4) Presence of some minerals in soil