Multiple choice question for engineering
Set 1
1. The characterisation of auger spectroscopy can be achieved up to which of the following depths?
a) 1 nm
b) 2 nm
c) 4 nm
d) 8 nm
Answer
Answer: a [Reason:] The characterisation of auger spectroscopy can be achieved up to a depth of 1nm. Best instruments can characterise few nm.
2. Auger electron spectroscopy can be used for surface chemical analysis in a way similar to which of the following?
a) ESCA
b) SIMS
c) ISS
d) Ion spectroscopy
Answer
Answer: a [Reason:] Auger electron spectroscopy can be used for surface chemical analysis in a way similar to ESCA. ESCA is also known as X-ray photoelectron spectroscopy.
3. AES is limited when it comes to very high resolution studies.
a) True
b) False
Answer
Answer: a [Reason:] AES is limited when it comes to very high resolution studies. It is very characteristic for various elements.
4. Qualitative chemical analysis is very often performed using which of the following?
a) ESCA
b) SIMS
c) AES
d) Ion spectroscopy
Answer
Answer: c [Reason:] Qualitative chemical analysis is very often performed using AES. Auger nomenclature follows the old x-ray notation.
5. Electron ionization can produce which of the following?
a) ESCA electron
b) Auger electron
c) Ion
d) Photon
Answer
Answer: b [Reason:] Electron ionization can produce Auger electron. Photo-ionisation can also produce Auger electron.
6. Electron ionisation can produce ESCA electrons.
a) True
b) False
Answer
Answer: b [Reason:] Electron ionisation cannot produce ESCA electrons. It can produce only Auger electrons.
7. Which of the following is an Auger transition starting from a hole in 1s levels which would be filled up from the 2p level?
a) KLM transition
b) KLL transition
c) LMN transition
d) LLM transition
Answer
Answer: b [Reason:] KLL transition is an Auger transition starting from a hole in 1s levels which would be filled up from the 2p level. 2p electron would also be emitted.
8. In ESCA process, the photon ejects which of the following?
a) 1s electron
b) 1p electron
c) 2s electron
d) 2p electron
Answer
Answer: a [Reason:] In ESCA process, the photon ejects 1s electron. For X-ray, an electron drops from the 2p orbit.
9. In Auger process, an electron drops to fill which of the following?
a) 1s hole
b) 1p hole
c) 2s hole
d) 2p hole
Answer
Answer: a [Reason:] In Auger process, an electron drops to fill 1s hole. It expels a 2p electron.
10. Auger electron spectroscopy involves the irradiation of the surface to be analysed with a beam of electrons of energy in the _________ range.
a) 1-2 KeV
b) 2-4 KeV
c) 4-8 KeV
d) 1-8 KeV
Answer
Answer: a [Reason:] Auger electron spectroscopy involves the irradiation of the surface to be analysed with a beam of electrons of energy in the 1-2 KeV range. Auger and X-ray emission are competitive processes.
11. In Auger spectroscopy, beam currents are typically _____ in a beam of diameter 0.5mm.
a) 5-10 µA
b) 5-20 µA
c) 5-30 µA
d) 5-50 µA
Answer
Answer: d [Reason:] In Auger spectroscopy, beam currents are typically 5-50 µA in a beam of diameter 0.5mm. Auger and X-ray emission are competitive processes.
12. Which of the following is the detection limit of Auger Electron Spectroscopy?
a) 0.1% monolayer
b) 0.5% monolayer
c) 1% monolayer
d) 2% monolayer
Answer
Answer: b [Reason:] The detection limit of AES is 0.5% monolayer. It has 0.5µ x-y resolution.
13. Which of the following denotes the sample destruction that occurs in Auger electron spectroscopy?
a) None in 95% of sample
b) None in 99% of sample
c) None in 100% of sample
d) Frequent
Answer
Answer: d [Reason:] Frequent sample destruction occurs in Auger electron spectroscopy. It is bad for organics.
14. How is the specificity of Auger electron spectroscopy?
a) Very bad
b) Bad
c) Good
d) Very good
Answer
Answer: c [Reason:] The specificity of Auger electron spectroscopy is good. ESCA has very good specificity.
15. AES is more sensitive than XPS because of which of the following factors?
a) Binding energies of electrons
b) Kinetic energies of electrons
c) Mass of electrons
d) Mass to charge ratio of electrons
Answer
Answer: b [Reason:] AES is more sensitive than XPS because of the difference in kinetic energies of electrons. Ion etching is sometimes necessary for AES.
Set 2
1. Given below is the diagram of Klystron tube. Identify the component.
a) Cathode
b) Anode
c) Grid
d) Reflector electrode
Answer
Answer: d [Reason:] The component is the reflector electrode. Cathode is on the left side and anode is in the middle.
2. Microwave frequency can be tuned over a small range by adjusting the distance between which of the following?
a) Cathode and anode
b) Anode and the reflector
c) Cathode and the reflector
d) Cathode and grid
Answer
Answer: c [Reason:] Microwave frequency can be tuned over a small range by adjusting the distance between anode and the reflector. Reflector voltage can also be adjusted.
3. Microwaves are generated by __________ and the power level is adjusted with the ________
a) Triode, rectifier
b) Pentode, attenuator
c) Klystron tube, attenuator
d) Diode, rectifier
Answer
Answer: c [Reason:] Microwaves are generated by klystron tube and the power level is adjusted with the attenuator. Klystron tube is a low power device.
4. Which of the following is also known as reflex oscillator?
a) Triode
b) Pentode
c) Special tube
d) Klystron tube
Answer
Answer: d [Reason:] Klystron tube is also known as the reflex oscillator. It is a low power device.
5. Microwaves reflected back from the cavity are routed to which of the following?
a) Attenuator
b) Klystron
c) Load
d) Diode detector
Answer
Answer: d [Reason:] Microwaves reflected back from the cavity are routed to diode detector. Power reflected from diode is absorbed by load.
6. Which of the following routes the microwaves entering from the klystron towards the cavity?
a) Oscillator
b) Attenuator
c) Circulator
d) Reflector
Answer
Answer: c [Reason:] Circulator routes the microwaves entering from the klystron towards the cavity. The sample is mounted in the cavity.
7. By introducing which of the following, signal-to- noise ratio can be improved?
a) Small amplitude field modulation
b) Large amplitude field modulation
c) Small amplitude field attenuation
d) Large amplitude field attenuation
Answer
Answer: a [Reason:] By introducing small amplitude field modulation, signal-to- noise ratio can be improved. This is because the previous DC measurement is too noisy.
8. Which of the following is adjusted as a fine control for frequency tuning?
a) Cathode
b) Anode
c) Reflector voltage
d) Grid
Answer
Answer: c [Reason:] Reflector voltage is adjusted as a fine control for frequency tuning. Distance is the coarse frequency adjustment.
9. In basic ESR spectrometer, the cavity length is adjustable.
a) True
b) False
Answer
Answer: b [Reason:] In basic ESR spectrometer, the cavity length is not adjustable. It is of one wavelength.
10. The cavity resonant frequency should be equal to which of the following?
a) Frequency of electric field
b) Klystron frequency
c) Frequency of magnetic field
d) Mechanical frequency
Answer
Answer: b [Reason:] The cavity resonant frequency should be equal to klystron frequency. It must be tuned in this manner.
11. When klystron frequency is close to the cavity resonant frequency, much less power is reflected from the cavity to the diode.
a) True
b) False
Answer
Answer: a [Reason:] When klystron frequency is close to the cavity resonant frequency, much less power is reflected from the cavity to the diode. It results in a dip in a power mode.
12. From which of the following are electrons emitted in the klystron tube?
a) Cathode
b) Anode
c) Grid
d) Reflector electrode
Answer
Answer: a [Reason:] The electrons are emitted by the cathode in the klystron tube. The cathode is heated.
13. Which of the following is the operating frequency of the ESR spectrometer?
a) 1.7 to 3.4 GHz
b) 1.5 to 4.2 GHz
c) 3.2 to 5.4 GHz
d) 8.8 to 9.6 GHz
Answer
Answer: d [Reason:] The operating frequency of the ESR spectrometer is 8.8 to 9.6 GHz. It is an important parameter.
14. At which of the following frequencies is the magnetic field at the sample modulated?
a) 1 kHz
b) 10 kHz
c) 100 kHz
d) 1000 kHz
Answer
Answer: c [Reason:] The magnetic field at the sample is modulated at 100 kHz. The magnetic field is kept at maximum.
15. The output of the klystron does not pass through which of the following?
a) Isolator
b) Reflector
c) Power leveller
d) Directional coupler
Answer
Answer: b [Reason:] The reflector is inside the klystron tube. The output passes through the other three components.
Set 3
1. Which of the following is not a characteristic of the immobilized enzymes?
a) They cannot be re-used
b) It produces reproducible results
c) Stability exists
d) Same catalytic activity is present for number of analysis
Answer
Answer: a [Reason:] Immobilized enzymes can be reused. This ensures that the same catalytic activity is present for a number of analyses.
2. Which of the following is the physico-chemical component?
a) Enzymes
b) Anti-bodies
c) Transducer
d) Cells or tissues
Answer
Answer: c [Reason:] Transducer is referred to as the physico-chemical component. Enzymes and anti-bodies are biological components.
3. An example of bio sensor, urea electrode makes use of which of the following electrodes?
a) Carbon dioxide electrode
b) Ammonia electrode
c) Fluoride electrode
d) Ammonium electrode
Answer
Answer: d [Reason:] An example of bio sensor, urea electrode makes use of the ammonium electrode. A urease membrane is also present.
4. In glucose electrode, glucose oxidase has been coupled to an electrode by which of the following materials?
a) Ferrocene derivatives
b) Urease
c) Polyacrylamide
d) Biochips
Answer
Answer: a [Reason:] In glucose electrode, glucose oxidase has been coupled to an electrode by using ferrocene derivatives. It is used to measure blood glucose in diabetic patients.
5. Biosensors measure glucose concentrations between which of the following ranges?
a) 10-1 to 10-2 M
b) 10-2 to 10-4 M
c) 10-1 to 10-4 M
d) 10-1 to 10-7 M
Answer
Answer: d [Reason:] Biosensors measure glucose concentrations between 10-1 to 10-7 M. It is linear in the range of 10-2 to 10-4 M.
6. Transducers employed in the bulk of enzyme electrodes use which of the following principles?
a) Amperometric
b) Optical
c) Magnetic
d) Colorimetric
Answer
Answer: a [Reason:] Transducers employed in the bulk of enzyme electrodes use amperometric principle. It may also use potentiometric principle.
7. Which of these biosensors use the principle of heat released or absorbed by a reaction?
a) Potentiometric biosensor
b) Optical biosensors
c) Piezo-electric biosensors
d) Calorimetric biosensors
Answer
Answer: d [Reason:] Calorimetric biosensors use the principle of heat released or absorbed by a reaction. The heat is measured to determine the concentration.
8. Which of the following biosensors use the movement of electrons produced during redox reactions?
a) Amperometric biosensor
b) Potentiometric biosensors
c) Piezo-electric biosensors
d) Optical biosensors
Answer
Answer: a [Reason:] Amperometric biosensor uses the movement of electrons produced during redox reactions. Redox reactions involve both reduction and oxidation.
9. Nanoscopic optical biosensors have fast response time but the sensitivity is reduced.
a) True
b) False
Answer
Answer: b [Reason:] Nanoscopic optical biosensors have fast response. They also have excellent biochemical sensitivity.
10. Given below is the diagram of biosensor. Identify the unmarked component.
a) Microprocessor
b) Filter
c) Transducer
d) A/D converter
Answer
Answer: c [Reason:] The biological signals must be converted into electrical signals. Transducers are used for this purpose.
11. In glucose sensor, a measure of change in oxygen value is a measure of the glucose value.
a) True
b) False
Answer
Answer: a [Reason:] In glucose sensor, a measure of change in oxygen value is a measure of the glucose value. It is then processed and displayed.
12. For constructing the glucose sensor, which of the following is used as gel?
a) Urea
b) Urease
c) Acrylamide
d) Polyacrylamide
Answer
Answer: d [Reason:] For constructing the sensor, polyacrylamide is used as the gel. It is used to entrap the glucose oxidase.
Set 4
1. Tandem mass spectroscopy combines which of the following devices?
a) Mass spectrometer and gas-solid chromatograph
b) Mass spectrometer and gas-liquid chromatograph
c) Mass spectrometer and gas chromatograph
d) Mass spectrometer and mass spectrometer
Answer
Answer: d [Reason:] Tandem mass spectroscopy combines two mass spectrometers. It is represented as MS/MS.
2. In tandem spectroscopy, the first stage sepatation device is a mass spectrometer.
a) True
b) False
Answer
Answer: a [Reason:] In tandem spectroscopy, the first stage sepatation device is a mass spectrometer. It is represented as MS/MS.
3. Which of the following is used to separate a single mass that is characteristic of a given analyte in a mixture?
a) First mass spectrometer
b) Second mass spectrometer
c) Filter
d) Precursor
Answer
Answer: a [Reason:] First mass spectrometer is used to separate a single mass that is characteristic of a given analyte in a mixture. The single mass is known as the precursor.
4. The mass-selected ions are activated in which of the following ways that causes them to fall apart to produce product ions?
a) Collisional activation
b) Evaporational activation
c) Inert gas activation
d) Thermal activation
Answer
Answer: a [Reason:] The mass-selected ions are activated by some means that cause them to fall apart to produce product ions. They are activated by collisional activation.
5. The final MS/MS spectrum consists only of product ions from the selected precursor.
a) True
b) False
Answer
Answer: a [Reason:] The final MS/MS spectrum consists only of product ions from the selected precursor. The chemical background and other mixture components are absent.
6. In reverse-geometry mass spectrometer which of the following precedes the electric sector?
a) Nebulizer
b) Orifice
c) Magnetic sector
d) Mass spectrometer
Answer
Answer: c [Reason:] In reverse-geometry mass spectrometer magnetic sector precedes the electric sector. Early work on MS/MS was done with reverse-geometry double focussing mass spectrometer.
7. A magnetic sector alone can be used as a mass spectrometer, with roughly _____ resolution.
a) Low
b) High
c) Unit
d) Infinite
Answer
Answer: c [Reason:] A magnetic sector alone can be used as a mass spectrometer, with roughly unit resolution. Early work on MS/MS was done with reverse-geometry double focussing mass spectrometer.
8. What does the acronym ‘MIKES’ stand for?
a) Mass-analysed ion kinetic energy spectrometer
b) Mass-based induced kinetic energy spectrometer
a) Mass invasive kinetic electric spectrometer
a) Mass-analyser in kinetic energy-type spectrometer
Answer
Answer: a [Reason:] ‘MIKES’ stands for mass-analysed ion kinetic energy spectrometer. It is related to spectrometers having magnetic field sectors.
9. In MIKES experiments which of the following are measured?
a) Product ions
b) Product ion kinetic energies
c) Product ions mass to charge ratio
d) Product ions masses
Answer
Answer: b [Reason:] In MIKES experiments, mass to charge ratios are not measured. Product ion kinetic energies are measured in these experiments.
10. All ions with the same number of charges will have __________
a) Same kinetic energy
b) Different kinetic energies
c) Same mass
d) Different mass
Answer
Answer: a [Reason:] All ions with the same number of charges will have same kinetic energy. It is assumed that all ions have a single charge.
11. A tandem mass spectrometer has which of the following analysers?
a) Time of flight mass analyser
b) Magnetic deflection analyser
c) Radiofrequency analyser
d) Quadrupole analyser
Answer
Answer: a [Reason:] A tandem mass spectrometer has a filter. The filter is followed by time of flight mass analyser.
12. Which of the following filters are used in tandem spectrometer?
a) Quadrupole mass filter
b) Low energy filter
c) High energy filter
d) Time of flight mass filter
Answer
Answer: a [Reason:] A tandem mass spectrometer has a quadrupole mass filter. The filter is followed by an analyser.
13. B/E scan is which of the following scans?
a) Product ion scan
b) Precursor ion scan
c) Mass scan
d) Charge scan
Answer
Answer: a [Reason:] B/E ratio can be chosen to select ions with a given velocity. It is a product ion scan.
14. Which of the following is located in the region between two analysers?
a) Nebuliser
b) Collision cell
c) Filter
d) Vacuum chamber
Answer
Answer: b [Reason:] Collision cell is located in the region between two analysers. Low energy parent ions are mass analysed.
15. Given below is the diagram of the drift tube of a tandem quadrupole/time of flight instrument. Identify the unmarked component.
a) Nebuliser
b) Filter
c) Chopper
d) Acceleration lens
Answer
Answer: d [Reason:] The unmarked component is acceleration lens. A collision cell is located before the acceleration lens.
Set 5
1. In combination electrode, which of the following electrodes are built together?
a) Primary electrode, secondary reference electrode
b) Primary reference electrode, glass electrode
c) Glass electrode, secondary reference electrode
d) Glass electrode with another glass electrode
Answer
Answer: c [Reason:] In combination electrode, glass electrode and secondary reference electrode are built together. Internal reference electrode is identical with external reference electrode.
2. Which of the following reference electrodes are used as internal and external reference electrodes in combination electrodes?
a) Silver/silver chloride electrode
b) Calomel electrode
c) Mercury/mercury sulphate electrode
d) Mercury/mercury chloride electrode
Answer
Answer: a [Reason:] Silver/silver chloride electrode is used as internal and external reference electrodes in combination electrodes. Internal reference electrode is identical with external reference electrode.
3. The reference electrodes in combination electrodes are protected against light using which of the following?
a) Emerald green glass
b) Ruby red glass
c) Sapphire blue glass
d) Pearl white glass
Answer
Answer: b [Reason:] The reference electrodes in combination electrodes are protected against light using ruby red glass. The ruby red glass absorbs light.
4. Combination electrodes containing the electrolyte in gel format have which of the following advantages over normal ones?
a) Simple to use
b) Low maintenance
c) Low cost
d) More accurate
Answer
Answer: b [Reason:] Combination electrodes containing the electrolyte in gel format provide the advantage of low maintenance. They are more rugged.
5. Which of the following is not the advantage of gel-filled electrodes?
a) Low maintenance
b) Rugged in construction
c) Easy to maintain
d) Does not cause clogging
Answer
Answer: d [Reason:] Gel-filled electrodes cause clogging. Hence, the output becomes less accurate.
6. Good choice for storing combination electrodes is in a buffer solution having which of the following pH?
a) pH1
b) pH2
c) pH3
d) pH4
Answer
Answer: d [Reason:] Good choice for storing combination electrodes is in a buffer solution having pH4. They can be stored in KCl solutions having particular pH values.
7. The gel used in combination electrodes does not have which of the following characteristic?
a) Non-toxic
b) USP grade
c) Inorganic material
d) Polyacrylamide
Answer
Answer: c [Reason:] The gel used in combination electrodes is organic. It can also be made of polyacrylamide.
8. Beckman coulter gel filled combination electrodes provide which of the following features to overcome various problems that occur in gel filled electrodes?
a) Filters
b) Semi-permeable membrane
c) Gas-permeable membrane
d) Micro-pore junction
Answer
Answer: d [Reason:] Beckman coulter gel filled combination electrode provides a special micro-pore junction to overcome various problems that occur in gel filled electrodes. Here, there is direct contact between sample and the gel.
9. In which of the following solutions must combination electrodes be soaked after cleaning?
a) KCl
b) LiCl
c) KNO3
d) K2SO4
Answer
Answer: a [Reason:] Combination electrodes can be soaked in KCl solution after cleaning. This will re-condition the bulb and increases its life.
10. Gel filled combination electrodes operate in a wide temperature range.
a) True
b) False
Answer
Answer: a [Reason:] Gel filled combination electrodes operate in a wide temperature range. The temperature range is between -5 to 100oC.
11. In combination electrodes, both the electrodes must be maintained at different temperatures.
a) True
b) False
Answer
Answer: b [Reason:] In combination electrodes, both the electrodes must be maintained at same temperature. Measuring error due to small temperature differences between the buffer solution and the sample are negligible.