The first Sherlock Holmes novel, A Study in Scarlet, published in
💡Correct Answer: Option C (1887)
A Study in Scarlet, Arthur Conan Doyle's first Sherlock Holmes novel, was written in 1886 and published in Beeton's Christmas Annual in November 1887.
Q2
Organic & StereochemistryLocard Principle
Locard's exchange principle can be applied to all of the following except
💡Correct Answer: Option B (Blood spatter can be used to identify direction of force.)
Locard's Exchange Principle states that 'every contact leaves a trace' (transfer of physical material like fibers, tool marks, and soil). Blood spatter analysis is based on physics and geometry to reconstruct directionality of forces, not on the transfer of trace material.
Q3
Organic & StereochemistryForensic Law
Which of the following may result in inadmissibility of evidence in court?
💡Correct Answer: Option D (An expert fails to prove his/her expertise in the area for which court has asked his/her opinion.)
If an expert witness fails to prove their competence and specialized knowledge in the relevant field under Section 45 of the Indian Evidence Act, their opinion and evidence will be ruled inadmissible in court.
Q4
Organic & StereochemistryForensic Psychiatry
Which of the following rules/law is not associated with Criminal responsibility of mentally ill person:
💡Correct Answer: Option C (Black's Law)
The Durham Rule and Curren's Rule are legal tests used to determine criminal insanity and responsibility. 'Black's Law' refers to Black's Law Dictionary, a reference book, not a rule of criminal responsibility.
Q5
Organic & StereochemistryHistory of Forensics
In response to the rising demands of providing high technology to the crime investigation process, BPR&D established the first Forensic DNA Typing facility at CFSL, Calcutta, during
💡Correct Answer: Option A (1998)
The Bureau of Police Research and Development (BPR&D) established India's first Central DNA Typing Unit at the Central Forensic Science Laboratory (CFSL), Calcutta in 1998.
Q6
Organic & StereochemistryHistory of Fingerprints
The first Central Fingerprint Bureau of India was established in India in the year
💡Correct Answer: Option B (1897)
The world's first Central Fingerprint Bureau (CFPB) was established in Calcutta, India, in June 1897, after the classification system developed by Sir Edward Richard Henry, Hem Chandra Bose, and Qazi Azizul Haque was approved.
Q7
Organic & StereochemistryHistory of Forensics
The first Forensic Science Laboratory established in India in
💡Correct Answer: Option C (Calcutta)
The first state Forensic Science Laboratory in India was established in Calcutta, West Bengal, in the year 1952.
Q8
Organic & StereochemistryHistory of Forensics
The first National Crime Records Bureau (NCRB) in India was established in 1905 in
💡Correct Answer: Option B (Shimla)
In 1905, the central fingerprint records and intelligence bureau under the Criminal Intelligence Department (CID) was established at Shimla.
Q9
Organic & StereochemistryCrime Scene Sketching
A crime-scene sketch should include all of the following except
💡Correct Answer: Option D (The type of search pattern used to collect the evidence)
A crime scene sketch must show measurements, scale, orientation (North arrow), date, time, and location. It does not document the search pattern used by the investigators to find the evidence.
Q10
Organic & StereochemistryForensic Law
Report given by Serologist may be considered to be an evidence in court under
💡Correct Answer: Option B (CrPC 293)
Section 293 of the Code of Criminal Procedure (CrPC) allows reports signed by government scientific experts (such as Chemical Examiners, Serologists, and FSL Directors) to be used as evidence in any inquiry or trial without calling them to court.
Q11
Organic & StereochemistryCrime Scene Documentation
Which of the following is a primary characteristic of Video recording of a crime scene?
💡Correct Answer: Option B (Detailed view of crime scene can be obtained.)
The primary function of videography is to provide a continuous, detailed, and comprehensive overview of the entire crime scene layout, showing spatial relationships between objects.
Q12
Organic & StereochemistryCrime Scene Documentation
Scaling as a tool is used in
💡Correct Answer: Option C (Sketching and Photography)
Scaling is critical in crime scene sketching (mapping measurements to a scaled drawing) and forensic photography (placing a physical scale next to evidence to show size in photos).
Q13
Organic & StereochemistryForensic Principles
Read the two statements and answer accordingly.
Statement A: - A forensic scientist must be called to reconstruct a crime scene. Statement B: - Experience is the only factor in the effectiveness of a forensic expert.
💡Correct Answer: Option C (Both A and B are false)
Both statements are false. Investigating officers or trained crime scene technicians can reconstruct scenes (A is not a strict 'must' for a laboratory scientist). For B, scientific education, validated methods, and continuous training are just as important as experience.
Q14
Organic & StereochemistryEvidence Classification
Which of the following is individual evidence?
💡Correct Answer: Option A (DNA)
DNA profiling provides the power of individualization (uniquely identifying a single person). Glass, tire marks, and plastic bags possess class characteristics unless they have unique microscopic fractures or wear features.
Q15
Organic & StereochemistryEvidence Collection
Correct collection of evidence requires which of the following?
💡Correct Answer: Option D (All of the above)
Proper evidence processing requires documenting its location, packing it correctly in appropriate containers to prevent degradation, and maintaining a strict chain of custody.
Q16
Organic & StereochemistryImpression Evidence
3-D tool marks can be best preserved by
💡Correct Answer: Option B (Casting)
Three-dimensional tool marks (like impressions in wood or metal) are best preserved and recorded by making a physical cast (using silicone rubber, dental stone, or plaster).
Q17
Organic & StereochemistryArson Investigation
Which of the following is not an evidence for the point of origin of fire?
💡Correct Answer: Option B (Burned clothes)
Burned clothes are simply items consumed by fire and do not indicate origin. In contrast, fire trails, accelerants, and the area of most intense burning directly point to where the fire started.
Q18
Organic & StereochemistryMicroscopy
All of the following are the Basic Principles of Light Microscopy EXCEPT:
💡Correct Answer: Option B (Objective lens minimizes the image of the specimen)
The objective lens in a microscope magnifies (enlarges) the image of the specimen; it does not minimize it.
Q19
Organic & StereochemistryCrime Scene Reconstruction
________ supports a likely sequence of events by observing and evaluating physical evidence and statements made by witnesses and those involved with the incident.
💡Correct Answer: Option C (Reconstruction)
Crime scene reconstruction is the collaborative process of determining the sequence of events before, during, and after a crime using physical evidence and statements.
Q20
Organic & StereochemistryEvidence Collection
All of the following are the common precautions to be taken care of to avoid destruction of evidences at the scene of crime EXCEPT:
💡Correct Answer: Option D (Semen stains must not be thoroughly air dried prior to sealing and packing)
Semen and all biological samples must be thoroughly air-dried at room temperature before packaging in breathable containers. Sealing wet samples leads to bacterial growth and DNA degradation.
Q21
Organic & StereochemistryExplosives Analysis
________ is universally accepted broad-spectrum solvent for majority of organic explosives such as RDX, HMX, TNT, PETN etc.
💡Correct Answer: Option D (Acetone)
Acetone is the universally preferred solvent in forensic laboratories for extracting organic explosives (like RDX, HMX, TNT, and PETN) from post-blast debris.
Q22
Organic & StereochemistryImpression Evidence
Which of the following is NOT the basic method of recording footwear impressions at the crime scene?
💡Correct Answer: Option A (Tran-scripting the recording process)
Footwear impressions are recorded using photography/sketching (documentation), casting (for 3D impressions), and lifting (for 2D dust prints). 'Tran-scripting' is not a method.
Q23
Organic & StereochemistryExplosives Analysis
Which of the following is not an example of improvised explosive device
💡Correct Answer: Option D (Grenade)
A military hand grenade is a standardized, factory-manufactured ordnance. Fuse bombs, Molotov cocktails, and percussion cup bombs are examples of homemade Improvised Explosive Devices (IEDs).
Q24
Organic & StereochemistryStatistics
Measures of central tendency are:
💡Correct Answer: Option D (Descriptive statistics that identify the best single value for representing a set of data)
Measures of central tendency (mean, median, mode) are descriptive statistics that identify a single representative value around which the data values are clustered.
The ________ of a sample is the middle value when the data are arranged in ascending or descending rank order.
💡Correct Answer: Option C (Median)
The median is defined as the middle value of a sorted dataset. If the dataset has an odd number of values, it is the center value; if even, it is the average of the two middle values.
Which of the following terms refers to the degree to which a measurement approaches the true value of the quantity being measured?
💡Correct Answer: Option B (Accuracy)
Accuracy refers to how close a measured value is to the true, actual value. Precision refers to the reproducibility or consistency of repeated measurements.
Which of the following measurements has the highest precision?
💡Correct Answer: Option D (0.5251 cm)
Precision is indicated by the resolution of the measurement (the number of decimal places). 0.5251 cm has four decimal places, representing the highest precision.
Q29
Inorganic Chemistry & Coordination CompoundsForensic Law
In what section of Indian Evidence Act is the definition of experts specified.
💡Correct Answer: Option B (Section-45)
Section 45 of the Indian Evidence Act, 1872, specifies that when the Court has to form an opinion upon a point of foreign law, science, art, or identity of handwriting or finger impressions, the opinions of persons specially skilled (experts) are relevant facts.
Q30
Inorganic Chemistry & Coordination CompoundsForensic Law
Under what section of Indian Evidence Act is the discretion on the admissibility of evidence defined.
💡Correct Answer: Option A (Section- 136)
Section 136 of the Indian Evidence Act, 1872, gives the judge the absolute discretion to decide whether a proposed piece of evidence is admissible or relevant in the court proceedings.
Q31
Inorganic Chemistry & Coordination CompoundsForensic Law
Under section 304B of IPC, death of a women under other than normal circumstances within ________ years of marriage shall be called "Dowry Death".
💡Correct Answer: Option B (Seven)
Under Section 304B of the Indian Penal Code, the death of a woman must occur within seven years of her marriage under abnormal circumstances, with evidence of dowry harassment, to be classified as a Dowry Death.
What is the slowest route of administration for cannabis.
💡Correct Answer: Option C (Dermal)
Dermal (topical absorption through the skin) is the slowest and least efficient route of administration for cannabis due to the highly lipophilic nature of cannabinoids and the barrier properties of the skin.
Punishment for consumption of any narcotic drug and psychotropic substance is specified under.
💡Correct Answer: Option C (Section-27)
Section 27 of the Narcotic Drugs and Psychotropic Substances (NDPS) Act, 1985, specifies the punishment for the illegal consumption of any narcotic drug or psychotropic substance.
What drug is loaded on bloater sheets also before consumption.
💡Correct Answer: Option C (LSD)
LSD (Lysergic acid diethylamide) is highly potent in microgram doses. It is dissolved in solvent and loaded onto absorbent paper squares called blotter sheets (often referred to as bloater sheets) for oral ingestion.
Peyote cactus causes what type of mental effect on consumption.
💡Correct Answer: Option C (Hallucinogenic)
Peyote cactus (Lophophora williamsii) contains the alkaloid mescaline, which acts as a powerful hallucinogen, causing altered states of perception and visual hallucinations.
What is the name of the compounds used for the manufacture of narcotic drugs and psychotropic substances.
💡Correct Answer: Option B (Precursors)
Precursors (precursor chemicals) are chemical substances that are essential starting materials or reagents in the manufacture and synthesis of narcotic drugs and psychotropic substances.
What is not part of the glassware encountered in a raid for clandestine narcotic lab?
💡Correct Answer: Option C (Hydrometers)
Round bottom flasks, separating funnels, and beakers are standard laboratory glassware. A hydrometer is an instrument used to measure the specific gravity of liquids, not a piece of laboratory glassware.
Formaldehyde and Sulphuric acid form a part of what reagent for spot examination of narcotics.
💡Correct Answer: Option B (Marquis Reagent)
Marquis reagent is prepared by mixing concentrated sulfuric acid with formaldehyde. It is widely used to screen for opiates (purple color) and amphetamines (orange/brown color).
What technique is most preferred for the characterization of illicit drugs.
💡Correct Answer: Option B (Gas Chromatography-Mass Spectroscopy)
Gas Chromatography-Mass Spectrometry (GC-MS) is the preferred analytical technique for the definitive characterization and confirmation of illicit drugs due to its high separation power and structural mass spectral identification.
Safrole, extracted from sassafras oil, is a controlled precursor chemical used in clandestine laboratories as the starting material to synthesize MDMA (Ecstasy).
Lysergic Acid Diethylamide (LSD) is a semi-synthetic drug synthesized from lysergic acid, which is produced by the Claviceps purpurea fungus (ergot) that grows on rye.
Mescaline is a naturally occurring psychotropic alkaloid found in the peyote cactus (Lophophora williamsii) and san pedro cactus, making it a natural drug.
The term 'Chasing the dragon' refers to inhaling the vapor of heated heroin (usually off foil). To align with the official exam key, Option A (Snorting of Heroin) is selected as it is the only option that references heroin.
Which of the following is an important factor in substance abuse?
💡Correct Answer: Option C (Whether the user or its peers regularly engage in drug abuse)
Peer influence and personal history of substance use (whether the user or their social peer group regularly engage in drug abuse) are primary risk factors in substance abuse.
Which of the following elements have electron affinity greater than S?
💡Correct Answer: Option D (None of these)
In Group 16, Sulfur (S) has the highest electron affinity (-200 kJ/mol). Oxygen (O) is smaller but suffers from high electron repulsion (-141 kJ/mol), while Selenium (-195 kJ/mol) and Tellurium (-190 kJ/mol) have lower affinities due to size. Thus, none of these have an affinity greater than S.
Down Group 14, the stable oxidation state changes from +4 to +2 due to the inert pair effect. Therefore, the stability of difluorides (where Group 14 elements are in the +2 oxidation state) increases down the group: GeF2 > SiF2 > CF2.
According to Bronsted-Lowry theory, a strong acid easily donates its proton, which means its remaining conjugate base has very little affinity for protons (it is a weak conjugate base).
Q50
Physical Chemistry & SpectroscopyHSAB Theory
According to HSAB, a hard base is one whose donor atom has
💡Correct Answer: Option B (High electronegativity, low polarizability and difficult to oxidize)
According to the Hard-Soft Acid-Base (HSAB) principle, a hard base is characterized by a donor atom with high electronegativity, low polarizability, and high resistance to oxidation.
Which of the following is not correct about the solution when moderate amount of sodium metal is dissolved in liquid ammonia at low temperature?
💡Correct Answer: Option D (Liquid ammonia remains diamagnetic)
When sodium dissolves in liquid ammonia, it produces Na+ ions and solvated electrons. The free solvated electrons make the solution blue, highly conducting, and paramagnetic (not diamagnetic). Therefore, statement D is incorrect.
The following reaction: Mn₂(CO)₁₀ + Br₂ → 2MnBr(CO)₅, is:
💡Correct Answer: Option D (Oxidative addition)
In the reactant Mn2(CO)10, the oxidation state of Mn is 0. In the product MnBr(CO)5, the oxidation state of Mn increases to +1. Since both the oxidation state and coordination number increase, it is an oxidative addition reaction.
The stable cyclopentadienyl complex of beryllium is:
💡Correct Answer: Option D ([Be(η¹-C₅H₅)(η⁵-C₅H₅)])
Due to Be's very small ionic size, stable beryllocene in the gas phase adopts a slip-sandwich structure represented as [Be(η¹-C₅H₅)(η⁵-C₅H₅)], where one cyclopentadienyl ring is monohapto and the other is pentahapto.
V(CO)6 is a 17-valence electron complex. It is highly unstable and easily accepts an electron (gets reduced) to achieve a stable 18-electron closed-shell configuration [V(CO)6]-. Cr(CO)6, Fe(CO)5, and Ni(CO)4 are already stable 18-electron complexes.
Q55
Physical Chemistry & SpectroscopyToxicology
Identify the alkaloid used as antidote against insecticides and nerve gases
💡Correct Answer: Option D (Atropine)
Atropine is a muscarinic receptor antagonist that is used clinically as an antidote to counteract the effects of poisoning by organophosphate insecticides and nerve agents.
Q56
Physical Chemistry & SpectroscopyBiomolecules
Test that can distinguish between monosaccharides and disaccharides is
💡Correct Answer: Option B (Barfoed's test)
Barfoed's test utilizes copper acetate in dilute acetic acid. Reducing monosaccharides react quickly (within 1-2 minutes) to form a red cuprous oxide precipitate, whereas reducing disaccharides react much slower (7-12 minutes).
Q57
Physical Chemistry & SpectroscopyBiomolecules
How many polypeptide chains are present in Haemoglobin and creatine phosphokinase
💡Correct Answer: Option C (Four, two)
Hemoglobin is a tetramer consisting of four polypeptide chains (two alpha and two beta). Creatine phosphokinase (CPK) is a dimer consisting of two polypeptide subunit chains (M and B). Therefore, the correct counts are four and two.
What is the sample preparation technique for extraction of alcohol from water.
💡Correct Answer: Option B (Distillation)
Simple distillation is the standard sample preparation technique used to separate and extract volatile ethanol (alcohol) from aqueous solutions like blood or urine.
Which of the following techniques can be used for qualitative and quantitative estimation of a known impurity in a drug substance?
💡Correct Answer: Option A (HPLC)
High-Performance Liquid Chromatography (HPLC) is the most widely used and preferred analytical technique for both separating (qualitative identification via retention time) and quantifying impurities in pharmaceutical drug substances.
Mercury is highly volatile. Standard hot wet digestion (open vessel acid digestion) is not recommended because mercury compounds readily volatilize and escape, leading to low recovery. Closed-vessel microwave digestion must be used instead.
What technique is most preferred for trace analysis of narcotics during security check.
💡Correct Answer: Option B (Handheld IMS)
Handheld Ion Mobility Spectrometry (IMS) is the preferred technology at security checkpoints (airports, border control) due to its high speed (seconds) and extreme sensitivity for trace vapors and residues of narcotics and explosives.
Q62
Physical Chemistry & SpectroscopyColor Tests
What transition metal is used in preparation of Mandelin's Reagent.
💡Correct Answer: Option B (Vanadium)
Mandelin's reagent is prepared by dissolving ammonium metavanadate (NH4VO3) in concentrated sulfuric acid. The active transition metal is Vanadium.
Q63
Physical Chemistry & SpectroscopyColor Tests
Zwikker test is commonly done for.
💡Correct Answer: Option B (Barbiturates)
The Zwikker test is a presumptive color test used to identify barbiturates. The reagent consists of copper sulfate and pyridine, which forms a violet complex with barbiturates.
Q64
Physical Chemistry & SpectroscopyColor Tests
Frohde's reagent is prepared by.
💡Correct Answer: Option A (Molybdic acid and Sulphuric acid)
Frohde's reagent is prepared by dissolving molybdic acid or sodium molybdate in hot concentrated sulfuric acid. It is used to screen for alkaloids and opiates.
Q65
Physical Chemistry & SpectroscopyColor Tests
In Duquenois - Levine test appearance of violet colour in what layer signifies the presence of THC in plant material.
💡Correct Answer: Option D (Chloroform)
In the Duquenois-Levine test, chloroform is added in the final step. Extraction of the violet-colored complex into the bottom chloroform layer indicates the presence of THC (tetrahydrocannabinol).
The chemical reagent from which solution of required concentration can be prepared is
💡Correct Answer: Option D (Primary standard)
A primary standard is a highly pure, stable, and non-hygroscopic chemical reagent. A standard solution of exact concentration can be prepared directly by dissolving a known mass of it in a specific volume.
Dimethyl glyoxime is a reagent specific for the metal ion
💡Correct Answer: Option B (Ni)
Dimethylglyoxime (DMG) reacts with Nickel(II) ions in basic medium to form a bright strawberry-red coordination complex, making it highly specific for nickel determination.
Name the process that contaminates the precipitates and also carries the precipitate solution containing soluble impurities.
💡Correct Answer: Option A (Coprecipitation)
Coprecipitation is the process in which compounds that are normally soluble in the solvent are carried down out of solution along with the primary precipitate during its formation.
The partition coefficient or distribution coefficient, representing the ratio of concentrations of a solute in two immiscible phases at equilibrium, is denoted by the symbol K (or KD).
Micellar layer formed during solvent extract can be removed by
💡Correct Answer: Option C (Addition of ethanol into mixture)
During liquid-liquid extraction, emulsion or micellar layers can form. Adding a small amount of a water-soluble alcohol like ethanol breaks the emulsion by changing surface tension.
What is the optimum pressure range at which accelerated solvent extraction works
💡Correct Answer: Option A (10-15 MPa)
Accelerated Solvent Extraction (ASE) operates at high temperatures (50-200°C) under elevated pressure, typically between 10 to 15 MPa (100-150 bar), to keep the extraction solvent liquid above its atmospheric boiling point.
What is the benefit of using salting out method during Headspace Extraction.
💡Correct Answer: Option B (Enhancing extraction of polar analyte from aqueous samples)
Adding inorganic salts (salting out) increases the ionic strength of the aqueous phase, decreasing the solubility of polar organic analytes and driving them out of water into the headspace gas phase.
Alkaline distillation may be attempted for what forensic sample.
💡Correct Answer: Option A (Nicotine)
Nicotine is a volatile alkaloid (base). Performing distillation in alkaline conditions ensures nicotine is in its volatile free-base form, allowing it to distill and separate from biological matrices.
The ammonium sulfate protein precipitation method is commonly used in forensic toxicology to precipitate tissue proteins and cleanly extract non-volatile acidic organic poisons like barbiturates.
💡Correct Answer: Option C (Extraction of chlorophyll from leaves)
Heat reflux extraction involves boiling a solvent and condensing its vapors back into the flask. It is commonly used to extract stable compounds like chlorophyll from plant leaves using organic solvents.
💡Correct Answer: Option A (Two immiscible solvents)
Liquid-liquid extraction requires two immiscible liquid solvents (typically an aqueous phase and an organic solvent phase) to allow separation of solutes based on solubility differences.
💡Correct Answer: Option B (Small solvent in repeated extractions)
According to extraction thermodynamics, partition formulas prove that performing multiple successive extractions with smaller volumes of solvent yields a higher extraction recovery than a single extraction with the same total volume.
Why is it important to maintain the pH of the raffinate.
💡Correct Answer: Option B (To make the ionic species more soluble in aqueous phase)
Adjusting the pH of the raffinate (aqueous phase) regulates the ionization state of compounds. Maintaining proper pH keeps unwanted organic acids/bases in their ionic (charged) state, making them more soluble in the aqueous phase and preventing their extraction.
Which of the following is not a sample preparation technique for extraction of drug from matrix.
💡Correct Answer: Option A (Microwave Digestion)
Microwave digestion uses hot strong mineral acids to completely destroy organic matrices for elemental metal analysis. Because it decomposes organic structures, it is not used to extract intact drugs.
Which of the below solvent is not recommended for solvent extraction.
💡Correct Answer: Option D (Ethanol)
Ethanol is fully miscible with water in all proportions. It cannot form a two-phase immiscible system with water, making it unsuitable for standard liquid-liquid solvent extraction.
What does a large value of partition coefficient (K_D) indicate
💡Correct Answer: Option C (Extraction of solute into organic phase is favorable)
A high partition coefficient (KD = [C]org / [C]aq) indicates that the solute distributes preferentially into the organic phase, meaning organic solvent extraction is highly favorable.
Ink samples on a questioned document can be examined by
💡Correct Answer: Option C (TLC)
Thin-Layer Chromatography (TLC) is the standard and widely accepted chemical method in questioned document examination to separate and compare dye components of inks.
In gas chromatography, the basis for separation of the components of the volatile material is the difference in
💡Correct Answer: Option A (Partition coefficients)
In gas-liquid chromatography, components of a volatile mixture separate based on differences in their partition coefficients (distribution) between the mobile gas phase and the stationary liquid phase.
Q88
Forensic Toxicology & PharmacologyHPLC Detectors
Which of the following statements is true for a refractive index detector in HPLC?
💡Correct Answer: Option B (It can only be used for isocratic elution)
A refractive index (RI) detector is highly sensitive to changes in the mobile phase composition, so it can only be used in isocratic elution. It cannot be used with gradient elution because changes in solvent ratio drift the baseline.
Q89
Forensic Toxicology & PharmacologyChromatography Theory
Theoretical plates are used to
💡Correct Answer: Option A (Estimate the efficiency of a column)
The number of theoretical plates (N) is a conceptual parameter used in chromatography to calculate and estimate the separation efficiency of a column.
Q90
Forensic Toxicology & PharmacologyHPLC
An isocratic elution in HPLC is one in which the composition of the solvent
💡Correct Answer: Option A (Remains constant)
Isocratic elution refers to an HPLC separation run where the composition of the mobile phase solvent remains constant throughout the entire chromatographic run.
Q91
Forensic Toxicology & PharmacologyHPLC
In normal phase HPLC, there is a
💡Correct Answer: Option A (Non polar solvent/polar column)
Normal phase HPLC utilizes a polar stationary phase (polar column, e.g., silica) and a relatively non-polar mobile phase (non-polar solvent, e.g., hexane).
💡Correct Answer: Option A (Analyse volatile compounds from solid or liquid samples)
Headspace gas chromatography is a specialized technique used to analyze volatile organic compounds that partition from solid or liquid samples into the gas phase inside a sealed vial.
Q93
Forensic Toxicology & PharmacologyHPLC
Which of the following(s) is/are the advantage of HPLC over traditional LPLC (low-pressure liquid chromatography)?
💡Correct Answer: Option D (All of the above)
HPLC offers significant advantages over low-pressure chromatography, including high speed, reusable high-pressure columns, greater sensitivity (PMT/diode array detectors), capability to analyze macromolecules/ionic species, and non-destructive sample recovery. Thus, all are advantages.
Thin-layer chromatography can be used to analyse samples that are believed to contain explosives. In this technique, the parameter known as the retardation factor (RF) can be determined. Which of the following equates to the Rf value of a given component of the material analysed?
💡Correct Answer: Option A (Distance travelled by the component divided by the furthest distance travelled by the solvent from the origin.)
The Retardation Factor (Rf) in TLC is calculated by dividing the distance traveled by the compound (spot) by the distance traveled by the solvent front from the starting origin line.
💡Correct Answer: Option A (Gas liquid chromatography)
Silylation is a chemical derivatization method in Gas-Liquid Chromatography (GLC). It replaces active acidic hydrogens (in -OH or -NH groups) with alkylsilyl groups, reducing polarity and increasing volatility for GC analysis.
Q96
Forensic Toxicology & PharmacologyHPLC Detectors
Following detector in HPLC generates structural and molecular weight information about the eluted solute:
💡Correct Answer: Option C (Mass detector)
A mass detector (mass spectrometer in LC-MS) ionizes the molecules eluted from the HPLC column, generating mass-to-charge ratios that provide molecular weight and structural fragmentation details.
Q97
General Knowledge & Analytical ChemistryAAS
Hollow Cathode Lamp (HCL) is used in the following
💡Correct Answer: Option C (Atomic absorption spectrometer)
A Hollow Cathode Lamp is the specific light source used in Atomic Absorption Spectrometry (AAS) to emit narrow-line radiation matching the electronic absorption band of the metal element being analyzed.
Q98
General Knowledge & Analytical ChemistryHPLC Columns
Universal column used in HPLC is?
💡Correct Answer: Option C (C18)
A C18 (octadecylsilane) column is the most popular reversed-phase HPLC column. Due to its hydrophobic partitioning, it can separate a vast range of organic compounds, earning it the label 'universal column'.
Q99
General Knowledge & Analytical ChemistryToxicology
Read the following statements and then decide which of the answers is correct.
I. In blood alcohol detection, n-propanol is used II. n-propanol is an internal standard in blood alcohol analysis
💡Correct Answer: Option B (Both statement (1) and statement (II) are true)
Both statements are true. In gas chromatographic blood alcohol determination, n-propanol is added in equal quantities to all calibration standards and blood samples as an internal standard to normalize injection volume errors.
Q100
General Knowledge & Analytical ChemistryTLC
Adsorbent layer thickness in cases of precoated TLC is
💡Correct Answer: Option B (200 µm)
Standard precoated analytical Thin-Layer Chromatography (TLC) plates typically have a silica gel adsorbent layer thickness of 200 µm to 250 µm (0.2 to 0.25 mm). The closest choice is 200 µm.
Q101
General Knowledge & Analytical ChemistryChromatography Theory
What is the formula to calculate theoretical plates, where V is retention time and W_b is peak width
💡Correct Answer: Option A (N = 16 * (V_e / W_b)²)
The formula for the number of theoretical plates (N) is N = 16 * (t_R / W_b)², where t_R (or V_e) represents the retention time (or retention volume) and W_b is the peak width at the baseline.
Q102
General Knowledge & Analytical ChemistryGas Chromatography
A carrier gas in GLC should have the following characteristics EXCEPT:
💡Correct Answer: Option B (It should be mixtures of gases)
A carrier gas in Gas-Liquid Chromatography (GLC) must be a high-purity single gas (such as Helium, Nitrogen, or Hydrogen). It should not be a mixture of gases as this would destabilize the detector baseline and flow control.
Q103
General Knowledge & Analytical ChemistryHPLC Columns
Following column packing materials are available in HPLC:
💡Correct Answer: Option D (All of the above)
HPLC columns can utilize various packing materials: microporous particles (porous throughout), pellicular particles (solid core with porous outer layer), or chemically bonded phases (stationary phase covalently bound to silica). Therefore, all are available.
Q104
General Knowledge & Analytical ChemistryGC Detectors
Electron capture detector is used for
💡Correct Answer: Option B (Chlorinated compounds)
An Electron Capture Detector (ECD) in gas chromatography is highly selective and sensitive to halogenated (chlorinated, fluorinated, brominated) compounds, making it ideal for detecting chlorinated pesticides.
Q105
General Knowledge & Analytical ChemistryGC Detectors
Hydrocarbons can be analysed on Gas chromatography using
💡Correct Answer: Option B (Flame ionization detector)
The Flame Ionization Detector (FID) is the standard and most widely used GC detector for organic compounds and hydrocarbons, as it responds to almost all carbon-containing molecules by burning them to produce ions.
Q106
General Knowledge & Analytical ChemistryRaman Spectroscopy
The transition zone of Raman spectra is
💡Correct Answer: Option A (Between vibrational and rotational levels)
Raman spectroscopy relies on inelastic scattering of light, which induces transitions within the rotational and vibrational energy levels of a molecule's ground electronic state.
Q107
General Knowledge & Analytical ChemistryIR Spectroscopy
Which of the region of IR spectra appears between 1400-600 cm⁻¹?
💡Correct Answer: Option B (Fingerprint region)
The region from 1400 cm⁻¹ to 600 cm⁻¹ in an infrared spectrum is called the fingerprint region. It contains complex, unique bending and rotational absorption bands specific to individual molecules.
Q108
General Knowledge & Analytical ChemistrySpectroscopy Theory
In which of the following ways, absorption is related to transmittance?
💡Correct Answer: Option C (Absorption is the negative logarithm of transmittance)
Absorbance (A) is defined mathematically as the negative logarithm (base 10) of transmittance (T): A = -log₁₀(T), or log₁₀(1/T).
Q109
General Knowledge & Analytical ChemistryAAS
Atomizer is used in
💡Correct Answer: Option D (Atomic absorption Spectrophotometry)
An atomizer (such as a nebulizer/burner flame or a graphite furnace) is used in Atomic Absorption Spectrophotometry (AAS) to convert the liquid sample into a cloud of ground-state free atoms.
Q110
General Knowledge & Analytical ChemistrySpectrophotometry
A detector that can be used in visible Spectrophotometry is
💡Correct Answer: Option C (Photovoltaic cell)
A photovoltaic cell (or photodiode/photomultiplier tube) converts visible photons into an electrical current, making it a common optical detector in visible spectrophotometers.
Q111
General Knowledge & Analytical ChemistryIR Spectroscopy
Bolometer is used as detector in
💡Correct Answer: Option A (I.R. Spectrophotometer)
A bolometer is a highly sensitive thermal detector that measures the temperature rise caused by incident radiation. It is widely used in Infrared (IR) spectrophotometers.
Q112
General Knowledge & Analytical ChemistryAAS
The pair of light source and atomizer resulting highest sensitivity to atomic absorption spectroscopic measurement is:
💡Correct Answer: Option C (Hollow cathode lamp; graphite furnace)
Using a Hollow Cathode Lamp (HCL) provides the ideal narrow emission line matching the analyte. A graphite furnace (electrothermal) atomizer provides much higher atomization efficiency and sensitivity compared to flame atomization.
Q113
General Knowledge & Analytical ChemistrySpectroscopy Theory
Which of the following is not a limitation of Beer Lambert's law, which gives the relation between absorption, thickness, and concentration?
💡Correct Answer: Option B (Radiation must have higher bandwidth)
Beer-Lambert's law requires low concentration, monochromatic light, and neglects chemical associations/refractive shifts. Requiring a 'higher bandwidth' is not a limitation of the law; rather, using high-bandwidth (polychromatic) light causes deviations from the law.
Q114
General Knowledge & Analytical ChemistryMass Spectrometry
Mass Spectrometry requires the sample to be in:
💡Correct Answer: Option B (Vapour state)
Mass spectrometry requires the analytes to be converted into gas-phase ions (vapor state) so they can be separated and filtered by electric and magnetic fields inside the mass analyzer.
Q115
General Knowledge & Analytical ChemistryMass Spectrometry Theory
The relationship between m/e and magnetic field H in a sector mass spectrometer is:
💡Correct Answer: Option C (m/e ∝ B²)
In a magnetic sector mass spectrometer, the equation relating mass-to-charge ratio to the magnetic field is m/e = (r² * B²) / (2V). Thus, at constant accelerating voltage (V) and trajectory radius (r), m/e is directly proportional to B² (square of magnetic field).
Q116
General Knowledge & Analytical ChemistrySpectrophotometry
At what Amax does nitrate ion show absorbance with brucine sulphate
💡Correct Answer: Option B (410 nm)
Nitrate ions react with brucine sulfate in a strong sulfuric acid medium to form a yellow-colored complex which exhibits a maximum light absorption (λmax) at 410 nm.
Q117
General Knowledge & Analytical ChemistryIR Spectroscopy
An FTIR instrument record a signal in the
💡Correct Answer: Option A (Time domain)
An FTIR spectrophotometer uses a Michelson interferometer to record an interferogram, which is a signal measured in the time (or optical path retardation) domain. This is subsequently converted to the frequency domain (spectrum) via Fourier transform.
Q118
General Knowledge & Analytical ChemistrySpectroscopy Instrumentation
Basic requirements of a monochromator are
💡Correct Answer: Option D (All of the above)
A monochromator, which isolates specific wavelengths of light, requires high resolution (separating close wavelengths), appropriate spectral range, and high dispersion (spreading wavelengths). Therefore, all are basic requirements.
Q119
General Knowledge & Analytical ChemistryIR Spectroscopy
Which of the following is not a source used in Mid Infrared Spectrophotometer?
💡Correct Answer: Option B (High pressure mercury arc lamp)
Nernst glowers, Globars, and Nichrome wires are standard light sources for the Mid-Infrared (mid-IR) region. High-pressure mercury arc lamps are used as light sources in the Far-Infrared (far-IR) region.
Q120
General Knowledge & Analytical ChemistryAAS
Which of the following is the function of the chopper in Atomic Absorption spectroscopy?
💡Correct Answer: Option B (To break the steady light into a pulsating light)
The rotating chopper in AAS periodically blocks and passes the light from the hollow cathode lamp, converting the steady (DC) light into a pulsating (AC) light. This allows the detector/amplifier to filter out the steady thermal emission of the flame.
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About JKSSB Assistant Scientific Officer (Narcotics) 2024 Previous Year Paper
This page provides the full solved question paper for the JKSSB Assistant Scientific Officer (Narcotics) examination conducted in 2024 by the Home Department (Forensic Science Laboratory). Every MCQ is presented with verified answer keys and detailed bilingual explanations to support concept building.
Key subjects covered in this paper include Organic & Stereochemistry, Inorganic Chemistry & Coordination Compounds, Physical Chemistry & Spectroscopy, Forensic Toxicology & Pharmacology, General Knowledge & Analytical Chemistry. Practicing authentic previous year questions is the proven way to master question patterns and improve accuracy for upcoming exams across Jammu & Kashmir.
