Analysers

• What is the drawback that occurs in using ion exchange chromatography on sulphonated polystyrene resin and colourimetry for amino-acid analysis? a) Less accuracy b) Low resolution c) Inconvenient to handle many individual samples d) Slow in operation

• Which one of the following methods is the most suitable for amino-acid analysis? a) Gas chromatography b) Ion exchange chromatography c) Paper electrophoresis d) Resin column chromatography

• Which of the following colour reagents are used in Resin column chromatography? a) Marquis reagent b) Benedict reagent c) Ninhydrin d) Nessler’s reagent

• Which of the following amino-acids is measured at a wavelength of 440nm using photometric systems? a) Proline b) Alanine c) Glutamine d) Valine

• In Automatic amino-acid analyzer, the sample containing ___________ of each amino compound is introduced at the top of the ion exchange column. a) 1 to 10 µmoles b) 1 to 10 moles c) 0.05 to 2 moles d) 0.05 to 2 µmoles

• Which of the following cannot be analysed using resin column chromatography? a) Peptides b) Amines c) Amino compounds d) Components which are ninhydrin negative

• Trapped air in pumps of Automatic amino-acid analyzer is eliminated using which of the following ways? a) Suction pump b) De-aerator c) Overcome naturally by pump pressure d) Using pulse damper

• Amino-acids are distinguishable from each other only by one or two atoms in their structure. a) True b) False

• What is the drawback that occurs in using gas chromatography for amino-acid analysis? a) Costly b) Cannot be used for proteins or polypeptides c) Slow process d) Complex in operation

• Resin column chromatography does not involve breaking of bonds in amino-acids. a) True b) False

• Which among the following gases have diamagnetic property (ability to be repelled by magnetic fields)? a) Oxygen b) Nitrogen c) Nitrogen dioxide d) Nitric oxide

• Which of the following gases have paramagnetic property (ability to get attracted to a magnetic field)? a) Nitric oxide b) Hydrogen c) Helium d) Nitrogen

• The force produced during the operation of Paramagnetic oxygen analyzer is proportional to which of the following? a) Magnetic susceptibility of sphere b) Magnetic susceptibility of surrounding gas c) Difference between magnetic susceptibility of sphere and magnetic field strength d) Difference between magnetic susceptibility of sphere and that of surrounding gas

• In Paramagnetic oxygen analyzer, the expression for magnitude of force produced can be expressed as, F = C (K-KO), where K= magnetic susceptibility of surrounding gas and KO= magnetic susceptibility of sphere. C denotes which of the following? a) Magnetic field strength b) Magnetic gradient c) Function of magnetic field strength and gradient d) Magnetic flux

• In Paramagnetic oxygen analyzer, the electrostatic force that is exerted should have which of the following features? a) It should be greater than the magnetic field and must be in the same direction b) It should be equal to the magnetic field and must be in the same direction c) It should be greater than the magnetic field and must be in the opposite direction d) It should be equal to the magnetic field and must be in the opposite direction

• Which of the following is true about the two charged vanes that produce electric field in Paramagnetic oxygen analyzer? a) Both the vanes should be at higher potential than the test body b) Both the vanes should have the same potential as the test body c) One vane should be at higher potential than the test body and the other vane should be at lower potential d) Both the vanes should be at lower potential than the test body

• To improve paramagnetic oxygen analyzer, the quartz suspension must be replaced with which of the following? a) Platinum-iridium b) Phosphor-bronze c) Gold-palladium d) Antimony

• In Paramagnetic oxygen analyzer, when no oxygen is present the magnetic force balances torque of the fibre. a) True b) False

• In the Beckman instrument, the flow rate recommended when the sample enters through a porous diffusion disc is which of the following? a) 100-200 cc/min b) 50-250 cc/min c) 40-60 cc/min d) 200-300 cc/min

• In the Beckman instrument, the flow rate recommended when the sample enters directly for rapid response is which of the following? a) 100-200 cc/min b) 50-250 cc/min c) 40-60 cc/min d) 200-300 cc/min

• If the oxygen content is not greater than 21%, which of the following gases must be used to set the span point? a) Oxygen b) Dry air c) Nitrogen d) Hydrogen

• Which of the following happens to the magnetic susceptibility of gases when the temperature changes? a) It increases with increase in temperature b) It decreases with increase in temperature c) It remains constant with increase in temperature d) It remains constant with decrease in temperature

• If the oxygen content is greater than 21%, which of the following gases must be used to set the span point? a) Oxygen b) Dry air c) Nitrogen d) Hydrogen

• Which of the following does not occur in Hartman and Braun oxygen analyzer based on the magnetic wind? a) Oxygen is attracted to the magnetic field b) Oxygen becomes less paramagnetic due to rise in temperature c) Resistance change in a resistance connected to the Wheatstone bridge occur d) Wheatstone Bridge becomes balanced due to temperature change