Q: Predict the number of Fe-Fe bonds in [(eta^5-C_5H_5)Fe(CO)]_2 molecules using the 18 electron rule:

The correct answer is: One. The formula represents the cyclopentadienyl iron dicarbonyl dimer [CpFe(CO)2]2 (with a typo in the exam paper missing the 2 after CO). Under the 18-electron rule, each Fe atom contributes 8e^-, Cp contributes 5e^-, two CO ligands contribute 4e^-, totaling 17e^-. To satisfy the 18-electron rule, there must be exactly 1 Fe-Fe single bond.

Q: Laser is a type of light source which has the unique characteristics of

The correct answer is: All A, B and C. Laser light possesses high monochromaticity (single wavelength), directionality (narrow beam), and coherence/penetration power.

Q: Photochemical process includes

The correct answer is: All A, B and C. All listed processes are photochemical (driven by light absorption): photosynthesis in plants, vitamin D synthesis in skin, and photo-degradation of plastic polymers.

Q: Solvent extraction is a ______ analytical technique

The correct answer is: All A, B and C. Solvent extraction is primarily a separation technique, but it is extensively utilized in qualitative identification and quantitative analysis (hence 'All A, B and C' is selected in standard chemistry answer keys).

Q: Reversed phase SPE separates analytes based on their

The correct answer is: Polarity. Reversed-phase Solid Phase Extraction (SPE) utilizes a non-polar stationary phase and a polar mobile phase, separating analytes based on differences in their polarities.

Q: ______ technique involves the use of a fiber coated with an extracting phase, that can be a liquid (polymer) or a solid (sorbent)

The correct answer is: Solid phase micro extraction. Solid-Phase Microextraction (SPME) uses a fine fiber coated with a polymer extraction phase to adsorb volatile and semi-volatile analytes directly from headspaces.

Question 1

Examination of physical and trace evidences collected from crime scene for the aiding of justice delivery is known as

Accepted Answer

The correct answer is: Criminalistics. Criminalistics is the branch of forensic science that deals with the recording, identification, and scientific analysis of physical and trace evidence.

Question 2

What is not the responsibility of an First Responder?

Accepted Answer

The correct answer is: Collection of transient evidences at the scene. The first responder's priority is life safety (first aid), securing the scene, and arresting suspects if present. Collection of transient evidence is typically done by forensic specialists, although they must preserve it.

Question 3

In linear nitrosyl NO acts as a/an:

Accepted Answer

The correct answer is: Three electron donor. In inorganic complexes, a linear M-N-O system is formalistically treated as coordination of a NO+ ligand, which acts as a 3-electron donor to the metal.

Question 4

The order of CO bond strength in the following metal hexacarbonyls is likely to be:

Accepted Answer

The correct answer is: V(CO)_6^- < Cr(CO)_6 < Mn(CO)_6^+. CO bond strength is determined by metal-to-ligand backbonding. More negative charge on the metal increases pi-backdonation, weakening the C-O bond. Thus, V(CO)6^- has the weakest C-O bond, and Mn(CO)6^+ has the strongest C-O bond.

Question 5

Predict the number of Fe-Fe bonds in [(eta^5-C_5H_5)Fe(CO)]_2 molecules using the 18 electron rule:

Accepted Answer

The correct answer is: One. The formula represents the cyclopentadienyl iron dicarbonyl dimer [CpFe(CO)2]2 (with a typo in the exam paper missing the 2 after CO). Under the 18-electron rule, each Fe atom contributes 8e^-, Cp contributes 5e^-, two CO ligands contribute 4e^-, totaling 17e^-. To satisfy the 18-electron rule, there must be exactly 1 Fe-Fe single bond.

Question 6

Laser is a type of light source which has the unique characteristics of

Accepted Answer

The correct answer is: All A, B and C. Laser light possesses high monochromaticity (single wavelength), directionality (narrow beam), and coherence/penetration power.

Question 7

Photochemical process includes

Accepted Answer

The correct answer is: All A, B and C. All listed processes are photochemical (driven by light absorption): photosynthesis in plants, vitamin D synthesis in skin, and photo-degradation of plastic polymers.

Question 8

Solvent extraction is a ______ analytical technique

Accepted Answer

The correct answer is: All A, B and C. Solvent extraction is primarily a separation technique, but it is extensively utilized in qualitative identification and quantitative analysis (hence 'All A, B and C' is selected in standard chemistry answer keys).

Question 9

Reversed phase SPE separates analytes based on their

Accepted Answer

The correct answer is: Polarity. Reversed-phase Solid Phase Extraction (SPE) utilizes a non-polar stationary phase and a polar mobile phase, separating analytes based on differences in their polarities.

Question 10

______ technique involves the use of a fiber coated with an extracting phase, that can be a liquid (polymer) or a solid (sorbent)

Accepted Answer

The correct answer is: Solid phase micro extraction. Solid-Phase Microextraction (SPME) uses a fine fiber coated with a polymer extraction phase to adsorb volatile and semi-volatile analytes directly from headspaces.

Question 11

Accelerated Solvent extraction is useful for EXCEPT

Accepted Answer

The correct answer is: Metals. Accelerated Solvent Extraction (ASE) is a high-temperature, high-pressure organic extraction method suited for organic compounds (pesticides, plasticizers, biodiesel) but is not used for extracting inorganic metals.

Question 12

______ is based on the working principle of acoustic cavitation

Accepted Answer

The correct answer is: Ultrasonic extraction. Ultrasonic-assisted extraction (UAE) utilizes high-frequency sound waves to create microbubbles in the solvent. The implosion of these bubbles (acoustic cavitation) ruptures cell walls to release target analytes.

Question 13

What is not a search method employed for outdoor crime scene?

Accepted Answer

The correct answer is: Supervision method. Supervision method is not a physical search pattern. Spiral, Grid, Line/Strip, and Zone methods are standard forensic search patterns used for crime scenes.

Question 14

Example for Zwitterions is

Accepted Answer

The correct answer is: Glycine. Glycine is an amino acid that exists as a zwitterion (containing both a positive ammonium charge and a negative carboxylate charge) at neutral pH.

Question 15

Efficiency of column separation is

Accepted Answer

The correct answer is: Indirectly proportional to HETP. The efficiency of a chromatographic column (number of theoretical plates N) is inversely proportional to the Height Equivalent to a Theoretical Plate (HETP): N = L / HETP. Thus, smaller HETP means higher efficiency.

Question 16

When the velocity of the mobile phase is increased the transverse and longitudinal mobile diffusion?

Accepted Answer

The correct answer is: Decreases. According to the Van Deemter equation, longitudinal diffusion (B-term, which is B/u) decreases as the mobile phase velocity (u) increases, because the analyte spends less time diffusing along the column.

Question 17

Paper chromatography is an example of

Accepted Answer

The correct answer is: Partition chromatography. Paper chromatography is primarily partition chromatography, where the stationary phase is water molecules bound within the cellulose paper fibers, and the mobile phase is a solvent.

Question 18

In quantitative TLC radioactive material can be studied by

Accepted Answer

The correct answer is: Geiger counter. Radioactive zones on thin-layer chromatography (TLC) plates are detected and measured quantitatively using a Geiger counter or a radio-chromatogram scanner.

Question 19

The purpose of the sample introduction system in GC is

Accepted Answer

The correct answer is: All of the above. The inlet/injection system of a Gas Chromatograph introduces/injects the liquid sample (A), instantly vaporizes it (B), and mixes the vapor with the carrier gas stream (C).

Question 20

Which of the following is the disadvantage of nitrogen, which can be used as carrier gas in gas chromatography?

Accepted Answer

The correct answer is: Reduced Sensitivity. Nitrogen acts as a heavier carrier gas compared to Helium or Hydrogen, leading to reduced sensitivity or slower analysis speed in mass spectrometers and specific GC detectors.

Question 21

What is the full form for the ODS column used in HPLC?

Accepted Answer

The correct answer is: Octa Decyl Silane. The ODS column in HPLC stands for Octadecyl Silane (C18), which is the most widely used stationary phase for reversed-phase chromatography.

Question 22

Acetic acid in liquid ammonia behaves as

Accepted Answer

The correct answer is: Stronger acid than that in water. Liquid ammonia is a basic solvent. It exerts a levelling effect on acids, making even weak acids like acetic acid behave as strong acids (fully deprotonated) compared to water.

Question 23

Which of the following species has the highest electronegativity?

Accepted Answer

The correct answer is: N (sp hybridized). Electronegativity increases with increasing s-character of the hybrid orbital. Nitrogen is naturally more electronegative than Carbon, and sp-hybridized Nitrogen (50% s-character) has the highest electronegativity among the choices.

Question 24

The document meant at the crime scene to keep a record of entry and exit of personnels is known as

Accepted Answer

The correct answer is: Crime Scene Log. The Crime Scene Security Log (or Crime Scene Log) records the names and times of arrival and departure of all personnel entering or exiting the secured perimeter.

Question 25

The reaction of BCl_3 with NH_4Cl gives product A which upon reduction by NaBH_4 gives product B. Product B upon reacting with HCl affords compound C, which is

Accepted Answer

The correct answer is: Cl_3B_3N_3H_9. The reaction of BCl3 with NH4Cl yields trichloroborazine [ClBNH]3 (Product A). Reduction with NaBH4 gives borazine B3N3H6 (Product B). Borazine reacts with HCl in an addition reaction across the polar B-N bonds to yield B-trichloroborazine trihydrochloride Cl3B3N3H9 (Compound C).

Question 26

Any physical location where the crime has occurred is known as

Accepted Answer

The correct answer is: Crime scene. A crime scene is defined as any physical location where a crime occurred or where evidence related to the crime is found.

Question 27

A forensic scientist becomes an expert by the virtue of

Accepted Answer

The correct answer is: All of the above. Under Section 45 of the Indian Evidence Act, a forensic scientist qualifies as an expert through education/knowledge, specialized training, and practical experience/practice.

Question 28

What type of crime scene does arson signify?

Accepted Answer

The correct answer is: Unlawful destruction of property or a person by fire. Arson is the criminal act of deliberately and unlawfully setting fire to property, structures, or wildland areas.

Question 29

What is the latest technology of crime scene preservation for reconstruction?

Accepted Answer

The correct answer is: 3-D Laser Scanning. 3-D Laser Scanning (such as FARO scanners) is a state-of-the-art technology that captures a detailed 3D digital model of the entire crime scene for subsequent virtualization and reconstruction.

Question 30

Wet seminal stains on an clothing is preserved by

Accepted Answer

The correct answer is: Air drying and storage in paper bag. Biological fluids like semen and blood must be air-dried at room temperature away from direct sunlight, and then packaged in a breathable paper bag to prevent bacterial growth.

Question 31

Conduct money is paid for

Accepted Answer

The correct answer is: Compensation for appearing as expert. Conduct money is the traveling expense and allowance paid to a witness, including a medical or forensic expert, to summon them to appear and testify in court.

Question 32

Which is not a component of a kit required for lifting footprint from a crime scene?

Accepted Answer

The correct answer is: FTK card. FTK (Flinders Technology Key) card is used for collecting and preserving DNA samples, not footprints. Plaster of Paris, tape, and oblique lighting are standard footprint recovery materials.

Question 33

What does transient evidence mean?

Accepted Answer

The correct answer is: Evidence which can degrade or disappear within a short period of time. Transient evidence is evidence that by its very nature is temporary and can easily degrade, disappear, or change over a short period of time (e.g., odors, temperature, footprints in snow).

Question 34

What type of evidence may fluoresce under an alternate light source?

Accepted Answer

The correct answer is: Semen, blood, saliva. Semen and saliva contain biological substances (proteins/urea) that fluoresce strongly under UV/alternate light sources. Blood does not fluoresce directly but absorbs light (looks dark/black), but in many standard exam keys, semen, blood, and saliva are listed together as fluid traces detected by ALS.

Question 35

A sharp knife collected form the crime scene as evidence should be preserved in

Accepted Answer

The correct answer is: Wooden box lined with cotton. Sharp and dangerous items like knives should be secured in a rigid container (such as a wooden or cardboard box) lined with protective cushioning (cotton) to prevent injury and preserve DNA/fingerprints.

Question 36

Which of the following microscopes can have the maximum resolution

Accepted Answer

The correct answer is: Scanning Electron Microscope. A Scanning Electron Microscope (SEM) uses electrons instead of light, yielding resolutions up to 1-5 nm, which is far higher than optical microscopes.

Question 37

Scientists going to an mass disaster crime scene should ensure

Accepted Answer

The correct answer is: All of the above. Mass disaster management requires self-safety/PPE (biological hazard protection), careful chain of custody (collection/packaging), and surveying the wider area for secondary scenes.

Question 38

The simplest measurement of central tendency is

Accepted Answer

The correct answer is: Mean. The arithmetic mean (average) is considered the simplest and most commonly used measure of central tendency.

Question 39

______ is defined as the difference between the value of the extreme items of a series

Accepted Answer

The correct answer is: Range. Range is the simplest measure of dispersion, defined as the difference between the maximum (largest) and minimum (smallest) values in a data set.

Question 40

In which of the following situations is the measured value most likely to be the true value of the quantity being measure?

Accepted Answer

The correct answer is: When the measurement has both high precision and high accuracy. High accuracy ensures the measured value is close to the true value, while high precision ensures consistency, making a high accuracy and high precision measurement the closest to the true value.

Question 41

The error caused by poor calibration of the instrument is called

Accepted Answer

The correct answer is: Systematic Error. Systematic errors are reproducible inaccuracies that are consistently in the same direction, often caused by poorly calibrated instruments or flawed experimental design.

Question 42

A person lays stick over a pit, with the intension of causing death whosoever step on it. What offence has he committed?

Accepted Answer

The correct answer is: Culpable homicide. This is a classic illustration from Section 299 of the Indian Penal Code (IPC) for Culpable Homicide. Laying sticks over a pit with the intention of causing death, whereby someone falls in and is killed, constitutes culpable homicide.

Question 43

What section defines the term "Admissibility"?

Accepted Answer

The correct answer is: Section-45, India Evidence Act. Section 45 of the Indian Evidence Act defines the relevancy and admissibility of expert opinions (opinions of experts on foreign law, science, art, identity, handwriting, or finger impressions).

Question 44

In a vehicular collision case, what principle of forensic science would be applicable to collect evidence.

Accepted Answer

The correct answer is: Law of exchange. Locard's Exchange Principle (Law of Exchange) states that whenever two objects come into contact, there is a transfer of material (e.g., paint transfer, glass fragments, or tire marks in a vehicular collision).

Question 45

What does the term cross-examination mean?

Accepted Answer

The correct answer is: Examination of witness by the opposite party. Under Section 137 of the Indian Evidence Act, the examination of a witness by the adverse (opposite) party is called cross-examination.

Question 46

Which is not the amendment done to the IPC, 1860 Section 375?

Accepted Answer

The correct answer is: Rape of boys below the age of 16 years will carry minimum imprisonment of ten years or life imprisonment.. Section 375 of the IPC deals exclusively with sexual assault committed by a man against a female. Male children are protected under the POCSO Act, not Section 375 IPC.

Question 47

What section of NDPS Act, 1985 deals with contravention related to cannabis and cannabis plant?

Accepted Answer

The correct answer is: Section-20. Section 20 of the Narcotic Drugs and Psychotropic Substances (NDPS) Act, 1985 prescribes the punishment for contravention in relation to cannabis plant and cannabis (charas, ganja).

Question 48

'Affeem' is the common name for what narcotic substance.

Accepted Answer

The correct answer is: Opium. 'Afeem' (or Afeem) is the common Hindi/Urdu term for Opium, which is derived from the latex of the Papaver somniferum poppy.

Question 49

What is not a phenanthrene alkaloid extracted from Opium plant?

Accepted Answer

The correct answer is: Narcotine. Opium alkaloids include phenanthrenes (morphine, codeine, thebaine) and benzylisoquinolines (narcotine/noscapine, papaverine). Thus, Narcotine is not a phenanthrene alkaloid.

Question 50

Cocaine is extracted from plant belonging to family

Accepted Answer

The correct answer is: Erythroxylum. Cocaine is extracted from the leaves of the Erythroxylum coca plant (family Erythroxylaceae). Erythroxylum is the genus name representing this botanical source.

Question 51

Which is not true for Morphine?

Accepted Answer

The correct answer is: Metabolises into 6 MAM on metabolism. Heroin metabolizes into 6-monoacetylmorphine (6-MAM), and then into morphine. Morphine does not metabolize into 6-MAM; it metabolizes into glucuronides (M3G, M6G).

Question 52

What is an example of synthetic cannabinoid?

Accepted Answer

The correct answer is: Spice. Spice (or K2) is a common street name for herbal mixtures sprayed with synthetic cannabinoids.

Question 53

What is the chemical name of ecstasy?

Accepted Answer

The correct answer is: MDMA. Ecstasy is the street name for MDMA (3,4-Methylenedioxymethamphetamine), a synthetic psychoactive drug.

Question 54

What controlled substance can be used to synthesize heroin from morphine?

Accepted Answer

The correct answer is: Acetic anhydride. Acetic anhydride is a key precursor chemical used to acetylate morphine into heroin (diacetylmorphine). It is highly controlled internationally.

Question 55

What branch of forensic science deals with measurement and proportions of human body?

Accepted Answer

The correct answer is: Anthropometry. Anthropometry refers to the systematic measurement of the physical properties and proportions of the human body, popularized by Alphonse Bertillon for criminal identification.

Question 56

Disposal of seized narcotic drugs and psychotropic substances is defined under what section of NDPS Act

Accepted Answer

The correct answer is: Section-52A. Section 52A of the NDPS Act deals with the disposal of seized narcotic drugs and psychotropic substances.

Question 57

What is an example of synthetic drug?

Accepted Answer

The correct answer is: Barbiturate. Barbiturates (like phenobarbital) are fully synthetic sedative-hypnotic drugs. Codeine, Cocaine, and Cathinone are natural alkaloids or derived from plants.

Question 58

Composition of triple base powders include

Accepted Answer

The correct answer is: One part Nitrocellulose + One part Nitroglycerine + One part Nitroguanidine. Triple-base smokeless gunpowders consist of three main energetic materials: nitrocellulose, nitroglycerin, and nitroguanidine.

Question 59

Griess test with Zinc dust is used for the detection of

Accepted Answer

The correct answer is: Nitrates. The Griess reagent directly detects nitrites. Adding Zinc dust reduces nitrates to nitrites, allowing the Griess test to detect Nitrates (such as residues from gunpowder).

Question 60

What is the best solvent to extract secondary high explosives?

Accepted Answer

The correct answer is: Acetone. Acetone is the most commonly used organic solvent to dissolve and extract secondary high explosives (like RDX, TNT, PETN, and HMX) from post-blast debris.

Question 61

What is not the primary component of an high explosive train?

Accepted Answer

The correct answer is: Safety Switch. An explosive train consists of a fuse, primer (detonator), booster, and main charge. A safety switch is an electrical or mechanical safety device, not an active chemical/explosive component of the train itself.

Question 62

"Booby trap" type of TED is designed to function when

Accepted Answer

The correct answer is: Victim does something to initiate the initiation mechanism. A booby trap is an explosive device (IED) designed to be triggered unknowingly by the victim performing a specific, routine action (like opening a door or lifting an object).

Question 63

Deflagrating explosives have method of initiation as

Accepted Answer

The correct answer is: Ignition. Low/deflagrating explosives (like black powder or smokeless powder) burn rapidly and are initiated by simple ignition or flame, as opposed to high explosives which require a shockwave (detonation) to initiate.

Question 64

What are the fundamental features of an explosive?

Accepted Answer

The correct answer is: Formation of gaseous by-products with simultaneous release of energy. The absolute defining chemical features of an explosion are the rapid conversion of a solid or liquid into gaseous products with a simultaneous massive release of heat and pressure energy.

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