JKSSB Assistant Scientific Officer (Chemistry and Toxicology) 2026 Solved Question Paper

Question 1

The first Chemical Examiner's Laboratory in India was established in:

Accepted Answer

Option A: 1849. The first Chemical Examiner's Laboratory in India was established in the Madras Presidency in 1849 to investigate suspected poisoning cases. Subsequently, laboratories were set up in Calcutta (1853), Agra (1864), and Bombay (1870).

Question 2

Arthashastra primarily emphasized forensic practices related to:

Accepted Answer

Option A: Toxicology and crime detection. Kautilya's ancient treatise 'Arthashastra' contains detailed descriptions of poisons, toxicological detection, testing food for royal security, recognizing poison symptoms, and investigating suspicious or unnatural deaths.

Question 3

The Central Forensic Science Laboratory (CFSL), Kolkata was established in:

Accepted Answer

Option B: 1952. The first Central Forensic Science Laboratory (CFSL) of India was initiated at Calcutta (Kolkata) in 1952 (and became fully operational with all specialized divisions in 1957 under the Ministry of Home Affairs). Among the given options, 1952 is the accepted official founding year.

Question 4

Which of the following tests was one of the first developed for Arsenic detection?

Accepted Answer

Option D: Marsh test. The Marsh test was developed by British chemist James Marsh in 1836. It was a pioneering, highly sensitive chemical test that transformed forensic toxicology by reliably detecting minute trace amounts of arsenic in biological tissues.

Question 5

Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R
Assertion (A): Securing the crime scene is the first step in investigation.
Reason (R): Evidence should always be collected before securing the scene.
In light of the above statements, choose the correct answer from the options given below

Accepted Answer

Option C: A is true but R is false. Assertion (A) is True because securing and isolating the scene is the crucial initial step to preserve physical integrity. Reason (R) is completely False because collecting evidence before establishing perimeter security risks contamination, loss, or destruction of critical evidence.

Question 6

Locard's exchange principle implies all of the following except

Accepted Answer

Option B: Blood spatter can be used to identify blood type.. Locard's Exchange Principle states that 'every contact leaves a trace'—referring strictly to mutual cross-transfer of physical trace materials (fibers, hairs, soil, dust). Using blood spatter pattern geometry to deduce blood type or velocity is a biological/physical analysis, not an example of physical material transfer.

Question 7

Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R
Assertion (A): Maintaining chain of custody ensures evidence integrity.
Reason (R): Evidence can be altered without documentation of custody.
In light of the above statements, choose the correct answer from the options given below

Accepted Answer

Option A: Both A and R are true and R is the correct explanation of A. Maintaining an unbroken chain of custody provides chronological documentation tracking every individual who collected, transported, analyzed, and safeguarded the evidence. Without such documentation, evidence can easily be tampered with or contaminated without detection, making R the exact reason why A is true.

Question 8

Which of these is the best method for crime scenes without physical barriers?

Accepted Answer

Option C: Spiral method. The spiral search method (inward or outward) is ideally suited for open outdoor areas without physical barriers or obstacles (such as open fields or water bodies), where an investigator can navigate in continuous concentric paths without obstruction.

Question 9

Which of the following are commonly used tools in crime scene investigation?
I. Tweezers and forceps
II. Magnifying lens
III. Evidence collection bags
IV. DNA sequencer
Choose the correct answer from the options given below:

Accepted Answer

Option C: I, II and III only. Tweezers/forceps, magnifying lenses, and evidence collection bags/containers are standard portable tools included in every CSI field kit. A DNA sequencer is a large, specialized laboratory instrument located in forensic genomics facilities, not carried to field crime scenes.

Question 10

Which of the following search methods are useful if a single investigator is present at a crime scene?
I. Grid pattern
II. Spiral pattern
III. Zone pattern
IV. Linear pattern
Choose the correct answer from the options given below:

Accepted Answer

Option D: I, II and IV only. A single searcher can effectively carry out Spiral, Linear (strip), and Grid searches across a scene. Zone (quadrant) search explicitly requires dividing the scene into sectors assigned to multiple team members or search teams, making I, II and IV the suitable patterns for a solo investigator.

Question 11

What is the first priority of a police officer at the crime scene?

Accepted Answer

Option A: The safety of all individuals in the area. The paramount initial priority of the first responder at any crime scene is the safety and medical assistance of all individuals present (preserving human life), followed by neutralizing active threats, and then securing the physical scene.

Question 12

Which of the following involves forming a hypothesis of the sequence of events from before the crime was committed through its commission?

Accepted Answer

Option A: Crime scene reconstruction. Crime scene reconstruction is defined as the scientific process of determining the sequence of events and formulating testable hypotheses regarding what transpired before, during, and after the commission of a crime based on physical evidence analysis.

Question 13

Which of the following deals with the making of sketch of an outdoor crime scene with large area by selecting the focal point?

Accepted Answer

Option C: Polar Method. The Polar Coordinates (Polar) Method uses a single known focal/datum point and measures the compass angle (azimuth) and direct line distance from that focal point to each item of evidence, making it ideal for mapping large, open outdoor crime scenes.

Question 14

Informational evidence obtained from statements of persons who have some knowledge of the crime scene are called as -

Accepted Answer

Option B: Testimonial evidence. Oral or written statements given by witnesses, victims, or suspects who possess first-hand knowledge or observation of a crime are categorized as Testimonial evidence (direct oral evidence).

Question 15

Which of the following variable can assume any numerical value over a certain interval?

Accepted Answer

Option B: Continuous Variable. A continuous variable can take an infinite number of possible real numerical values within any specified interval (such as blood alcohol concentration, temperature, or mass), unlike discrete variables which only take countable integer values.

Question 16

Which of the following methods use sample results to help make decisions or predictions about a population?

Accepted Answer

Option C: Inferential Statistics. Inferential statistics involves using data drawn from a sample to make generalizations, estimates, hypothesis tests, or predictions about an entire broader population.

Question 17

Which of the following distributions is used for hypothesis testing?

Accepted Answer

Option A: Chi-Squared Distribution. The Chi-Squared (χ²) distribution is a fundamental sampling distribution widely used in non-parametric hypothesis testing, notably goodness-of-fit tests and tests of independence between categorical variables.

Question 18

Which of the following scales shows equal intervals?
I. Nominal scale
II. Ordinal scale
III. Interval scale
IV. Ratio scale
Choose the correct answer from the options given below:

Accepted Answer

Option D: III and IV only. In Stevens' typology of measurement scales, both Interval and Ratio scales possess the mathematical property of equal units of distance (equal intervals) between consecutive numerical values. Nominal only categorizes, while Ordinal only ranks.

Question 19

Which of the following test is useful to find analysis of variance in a sample data?

Accepted Answer

Option B: F test. The F-test is the statistical test used in Analysis of Variance (ANOVA) to compare variances across two or more sample groups by calculating the ratio of between-group variance to within-group variance.

Question 20

Which of the following represent degree of symmetry in statistical calculation

Accepted Answer

Option C: Skewness. Skewness is a measure of the asymmetry or degree of departure from symmetry of a frequency distribution about its mean. A symmetric distribution has a skewness value of zero.

Question 21

Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R
Assertion (A): Under the Bharatiya Nagarik Suraksha Sanhita (BNSS) 2023, forensic examination is mandatory in all offences punishable with imprisonment of seven years or more.
Reason (R): The law recognises that scientific evidence strengthens the fact-finding process and requires expert forensic involvement.
In light of the above statements, choose the correct answer from the options given below

Accepted Answer

Option A: Both A and R are true and R is the correct explanation of A. Section 176(3) of the Bharatiya Nagarik Suraksha Sanhita (BNSS), 2023 mandates that forensic experts must visit crime scenes and collect evidence for all offences punishable with 7 years or more of imprisonment. Reason (R) provides the exact legislative rationale for this statutory mandate.

Question 22

Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R
Assertion (A): Reports from government forensic experts are admissible in court without the expert's presence unless genuineness is challenged.
Reason (R): The Criminal Procedure law exempts government scientific experts from compulsory court attendance when their forensic report is accepted as evidence.
In light of the above statements, choose the correct answer from the options given below

Accepted Answer

Option A: Both A and R are true and R is the correct explanation of A. Under Section 293 of the Code of Criminal Procedure (and corresponding Section 329 of BNSS 2023), written reports of specified government scientific experts are directly admissible as evidence without examining the expert in person, unless summoned by the court or challenged by the defense.

Question 23

Which statement best reflects the judicial view of expert testimony?

Accepted Answer

Option C: Expert opinion aids but does not bind the court. Under Indian Evidence Law (Section 45 IEA / Section 39 Bharatiya Sakshya Adhiniyam), expert opinion is advisory in nature. The Supreme Court of India has consistently held that expert opinion aids the court in evaluating technical facts but does not bind the judge, who remains the sole arbiter of facts.

Question 24

The primary objective of cross-examining an expert witness is to:

Accepted Answer

Option B: Expose possible errors or assumptions. Cross-examination of an expert witness aims to critically evaluate the scientific methodology, test underlying assumptions, examine testing conditions, and expose possible errors, limitations, or alternative interpretations in the expert's conclusions.

Question 25

Match the followings:
List - I
I. Barbiturates
II. MAO Inhibitors
III. LSD
IV. Cocaine
List - II
a. Stimulant
b. Depressant
c. Anti-Depressant
d. Hallucinogen
Choose the correct answer from the options given below:

Accepted Answer

Option D: I - b, II - c, III - d, IV - a. Barbiturates are CNS depressants (b). Monoamine oxidase (MAO) inhibitors are anti-depressants (c). LSD (Lysergic acid diethylamide) is a potent hallucinogen (d). Cocaine is a central nervous system stimulant (a). Thus, I-b, II-c, III-d, IV-a.

Question 26

When gelatin is mixed with a hallucinogen drug and cut into small squares, it is known as

Accepted Answer

Option D: Windowpanes. In illicit drug street terminology, LSD prepared in thin sheets of gelatin and cut into tiny transparent or coloured squares is called 'windowpanes' (or 'clearlight'). Microdots refer to tiny pills/tablets, while Orange Sunshine and Purple Haze refer to specific historic formulations.

Question 27

Which of the followings are synthetic opioids?
I. Morphine
II. Methadone
III. OxyContin
IV. Heroin
Choose the correct answer from the options given below:

Accepted Answer

Option C: II, III and IV only. Morphine is a purely natural opiate extracted directly from the opium poppy plant Papaver somniferum. Methadone is fully synthetic, while OxyContin (oxycodone) and Heroin (diacetylmorphine) are non-natural, laboratory-synthesized/semi-synthetic opioids. Therefore, the synthetic/chemically modified opioid group consists of II, III and IV.

Question 28

Which of the following chemicals are precursors for methamphetamine synthesis?
I. Ephedrine
II. Safrole
III. Caffeine
IV. Phenyl-2-propanone (P2P)
Choose the correct answer from the options given below:

Accepted Answer

Option B: I, II and IV only. Ephedrine (I) is reduced via red phosphorus/hydriodic acid to methamphetamine. Phenyl-2-propanone (P2P / BMK, IV) is converted via reductive amination to methamphetamine. Safrole (II) is a precursor in the broader amphetamine-designer class (specifically for MDMA/MDA). Caffeine (III) is strictly a cutting agent/adulterant, not a precursor. Hence, I, II and IV.

Question 29

According to SWGDRUG guidelines, which analytical technique is classified under Category A for the identification of controlled substances?

Accepted Answer

Option B: IR-Spectroscopy. Under Scientific Working Group for the Analysis of Seized Drugs (SWGDRUG) criteria, Category A techniques provide the highest structural discriminative power and include Infrared Spectroscopy (IR), Mass Spectrometry (MS), NMR, Raman Spectroscopy, and X-ray Diffractometry. GC and TLC are Category B; colour tests are Category C.

Question 30

Which of the following drugs come under the schedule III of controlled substance act?

Accepted Answer

Option D: Anabolic steroids and codeine. Under the Controlled Substances Act (CSA), Schedule III includes substances with moderate to low potential for physical dependence, such as Anabolic steroids and combination products containing limited amounts of codeine (e.g. Tylenol with codeine). Methadone and PCP are Schedule II.

Question 31

Which of the following plant poisons is commonly known as railroad poison?

Accepted Answer

Option B: Dhatura. In Indian forensic toxicology and legal medicine, Dhatura (Datura) is notoriously designated as the 'railroad poison' or 'highwayman's poison'. Thugs and criminals administer its crushed seeds in food, tea, or prasad to railway/bus passengers to induce stupor and coma for robbery.

Question 32

Naloxone is the specific antidote used in poisoning due to

Accepted Answer

Option A: Morphine. Naloxone is a pure competitive opioid receptor antagonist (specifically at mu-opioid receptors) used as the lifesaving antidote to rapidly reverse respiratory depression and coma in acute poisoning from Morphine, heroin, and other opioids.

Question 33

Which of the following is associated with sinsemilla?

Accepted Answer

Option A: Marijuana. Sinsemilla (Spanish for 'without seeds') refers to the unfertilized female flowering tops of the Cannabis sativa plant (Marijuana). Preventing pollination causes the plant to produce exceptionally high concentrations of THC-rich resin.

Question 34

Which of the following method adopted for the desirable effect of Khat?

Accepted Answer

Option D: Cheweing. Khat (Catha edulis), which contains the amphetamine-like stimulant alkaloid cathinone, is traditionally consumed by chewing the fresh leaves and shoots and holding the bolus against the inside of the cheek to allow buccal mucosal absorption.

Question 35

Match the followings:
Drug Name
I. Cannabis
II. Cocaine
III. Alcohol
IV. Brucine
Condition
a. Magnan's symptom
b. Opisthotonos
c. Run Amok
d. Delirium tremens
Choose the correct answer from the options given below:

Accepted Answer

Option A: I - c, II - a, III - d, IV - b. Cannabis intoxication can precipitate a frenzied homicidal state known as 'Run Amok' (c). Chronic cocaine use causes tactile hallucinations (cocaine bugs / Magnan's sign, a). Chronic alcohol withdrawal leads to Delirium tremens (d). Brucine (nux vomica spinal alkaloid) produces tetanic spinal convulsions resulting in Opisthotonos (b). Thus, I-c, II-a, III-d, IV-b.

Question 36

Which of the following is correct in Marquis test?
I. Opium - Purple colour
II. Amphetamine - orange brown colour
III. Opium - Orange colour
IV. Amphetamine - bluish Purple colour
Choose the correct answer from the options given below:

Accepted Answer

Option B: I and II only. In the Marquis presumptive color test (formaldehyde in concentrated sulfuric acid), opiates (Opium/Morphine/Heroin) produce a distinct purple/violet coloration (I), whereas amphetamines produce an orange to orange-brown color (II). Therefore, statements I and II are correct.

Question 37

Which of the following is synthesized through amine displacement method using safrole as the precursor?

Accepted Answer

Option B: MDMA. Safrole (found in sassafras oil) is converted via isomerization to isosafrole and oxidized to MDP2P (3,4-methylenedioxyphenyl-2-propanone). Reaction with methylamine followed by reduction yields MDMA (3,4-methylenedioxymethamphetamine).

Question 38

Match the followings:
Drug Name
I. Barbiturates
II. Benzodiazepine
III. LSD
IV. Cocaine
Identification Test
a. Ehrlich's test
b. Scott test
c. Dillie-Koppanyi test
d. Zimmermann test
Choose the correct answer from the options given below:

Accepted Answer

Option A: I - c, II - d, III - a, IV - b. Barbiturates are identified by the Dillie-Koppanyi test (cobalt acetate + isopropylamine -> violet, c). Benzodiazepines give a reddish-purple color with the Zimmermann test (d). LSD (an indole derivative) reacts with Ehrlich's reagent (p-DMAB) to give a purple color (a). Cocaine is presumptively identified by the Scott test (cobalt thiocyanate -> blue, b). Thus, I-c, II-d, III-a, IV-b.

Question 39

When phencyclidine is mixed with LSD, it is known as

Accepted Answer

Option A: Angel dust. Angel dust is the universally recognized street name for phencyclidine (PCP), which is frequently illicitly combined with or misrepresented as LSD on street markets. (Ice is crystal methamphetamine, Speed is amphetamine, and Rock is crack cocaine).

Question 40

A condition in which an individual inject amphetamine at every 2-3 hours is known as

Accepted Answer

Option C: Speed binge. A 'speed binge' (or 'run') is a pattern of severe amphetamine abuse where the user injects or consumes the drug every 2 to 3 hours over several days continuously to maintain a prolonged state of intense euphoria, foregoing food and sleep.

Question 41

Which of the following is a group of completely synthetic drugs?

Accepted Answer

Option C: LSD and PCP. PCP (Phencyclidine) and Barbiturates are completely synthetic laboratory chemicals. LSD (Lysergic acid diethylamide) is semi-synthetic (derived from ergot alkaloids), but in general toxicology test banks, synthetic hallucinogens (LSD and PCP) are grouped together as synthetic drugs compared to plant opioids like Heroin (semi-synthetic from opium) or Oxycodone.

Question 42

Which of the following are naturally occurring drug?
I. Marijuana
II. Psilocybin
III. Peyote
IV. LSD
Choose the correct answer from the options given below:

Accepted Answer

Option A: I, II and III only. Marijuana (from Cannabis sativa plant), Psilocybin (from Psilocybe genus magic mushrooms), and Peyote (from Lophophora williamsii cactus containing mescaline) are all naturally occurring plant/fungal drugs. LSD is a laboratory-synthesized compound. Therefore, I, II and III only.

Question 43

Which of the following is an active principle of dhatura?

Accepted Answer

Option A: Scopolamine. The principal active toxic alkaloids of Dhatura (Datura fastuosa/stramonium) are tropane alkaloids: Scopolamine (hyoscine), hyoscyamine, and atropine. Thevetin and Cerberin are cardiac glycosides from Yellow Oleander and Cerbera odollam respectively.

Question 44

Match the followings:
Drugs
I. Ketamine
II. Gamma-Hydroxybutyric acid
III. Rohypnol
IV. MDMA
Street Names
a. Liquid G
b. Rolls
c. Special K
d. Circles
Choose the correct answer from the options given below:

Accepted Answer

Option C: I - c, II - a, III - d, IV - b. Ketamine is widely known on the street as 'Special K' (c). Gamma-Hydroxybutyric acid (GHB) is known as 'Liquid G' (a). Rohypnol (flunitrazepam) is known as 'Circles' or 'roofies' (d). MDMA (Ecstasy) tablets are called 'Rolls' (b). Thus, I-c, II-a, III-d, IV-b.

Question 45

Which of the following is causing high psychological dependency but no physical dependency?

Accepted Answer

Option B: Cocaine. Cocaine is characterized by intense, overwhelming psychological dependence (intense craving) with minimal to no classic physical dependence (unlike opiates, barbiturates, or alcohol, which cause severe physical withdrawal syndromes with physiological autonomic disturbances).

Question 46

The hallucinogenic effects of LSD were first described by

Accepted Answer

Option C: Albert Hofmann. Swiss chemist Albert Hofmann first synthesized LSD-25 in 1938 at Sandoz Laboratories and personally discovered and documented its profound hallucinogenic psychopharmacological effects on April 16 and 19, 1943 (the famous 'Bicycle Day').

Question 47

Which of the following is a designer drug?

Accepted Answer

Option D: MDMA. MDMA (3,4-methylenedioxymethamphetamine) is the quintessential 'designer drug'—a chemically modified synthetic analogue created to alter pharmacological action (entactogen/empathogen) and historically circumvent controlled substance scheduling laws.

Question 48

Which of the following presumptive test give dull orange colour with psilocobin?

Accepted Answer

Option A: Marquis test. In presumptive spot testing, the Marquis reagent (formaldehyde in concentrated sulfuric acid) reacts with psilocybin/psilocin extracts to produce a characteristic dull orange to yellow-orange coloration.

Question 49

Which of the following is a group of cardiac poison?

Accepted Answer

Option C: Nicotine and Aconite. In forensic toxicological classification, cardiac poisons include Digitalis, Oleander, Nicotine, and Aconite. Aconite (Aconitum napellus) targets cardiac voltage-gated sodium channels causing fatal arrhythmias, while Nicotine exerts profound toxic action on cardiac autonomic ganglia.

Question 50

Which of the following is a combination of acid base drug?

Accepted Answer

Option A: Barbiturates - Phencyclidine. In analytical toxicology, Barbiturates (like phenobarbital) are weakly acidic drugs, whereas Phencyclidine (PCP) is a basic organic amine drug. Thus, the Barbiturates - Phencyclidine pair represents an acid-base drug combination.

Question 51

Which of the following is used for the isolation of organic non-volatile substances?

Accepted Answer

Option B: Solvent extraction. Solvent extraction (such as the classic Stas-Otto process and modified liquid-liquid extractions) is the universal analytical method used to isolate non-volatile organic poisons (alkaloids, barbiturates, pesticides) from biological viscera. Distillation isolates volatile poisons, and wet digestion isolates heavy metals.

Question 52

Which of the following benzodiazepines have shortest half-life period?

Accepted Answer

Option C: Alprazolam. Among the options listed, Alprazolam has the shortest elimination half-life of approximately 11–12 hours. Lorazepam has a half-life of 12–18 hours, whereas Medazepam and Diazepam are long-acting agents with active metabolite half-lives exceeding 30–100 hours.

Question 53

Mescaline is obtained from which of the following

Accepted Answer

Option B: Cactus. Mescaline (3,4,5-trimethoxyphenethylamine) is a naturally occurring psychedelic protoalkaloid found predominantly in the peyote cactus (Lophophora williamsii) and the San Pedro cactus.

Question 54

In which of the following class of the Explosive Act Rules, 1983, chlorate mixture is classified?

Accepted Answer

Option D: Class 4. Under the Indian Explosives Rules (1983 / 2008), explosives are classified into 8 categories: Class 1 is Gunpowder, Class 2 is Nitrate mixture, Class 3 is Nitro-compound, Class 4 is Chlorate mixture, Class 5 is Fulminate, Class 6 is Ammunition, and Class 7 is Fireworks.

Question 55

Which of the following is a tertiary explosive?

Accepted Answer

Option A: ANFO. Tertiary explosives (blasting agents) are extremely insensitive to shock and friction, requiring a substantial booster charge of a secondary explosive to initiate detonation. ANFO (Ammonium Nitrate Fuel Oil) is the classic tertiary explosive. PETN and HMX are secondary explosives; Dinol is primary.

Question 56

Which of the following is used in percussion cap of firearm ammunition?
I. Fulminates
II. Lead Azide
III. Lead Styphnate
IV. Dinol
Choose the correct answer from the options given below:

Accepted Answer

Option B: I and III only. Percussion caps in small arms ammunition historically relied on Mercury Fulminate (Fulminates - I) and modern non-corrosive primer mixtures rely predominantly on Lead Styphnate (III) along with barium nitrate and antimony sulfide. Lead azide is used in industrial blasting detonators, not small arms percussion caps. Hence, I and III only.

Question 57

Match the followings:
List - I Name of Explosive
I. Cyclotol
II. Pentolite
III. Terytol
IV. Octol
List - II Composition
a. HMX + TNT
b. RDX + TNT
c. PETN + TNT
d. TNT + Tetryl
Choose the correct answer from the options given below:

Accepted Answer

Option C: I - b, II - c, III - d, IV - a. Cyclotol is an explosive mixture of RDX and TNT (b). Pentolite consists of PETN and TNT (c). Tetrytol consists of Tetryl and TNT (d). Octol is an explosive blend of HMX and TNT (a). Therefore, the correct matching is I-b, II-c, III-d, IV-a.

Question 58

Why is it difficult to estimate the quantity of explosive used based solely on damage?

Accepted Answer

Option B: Confinement and environment alter damage. Blast damage is determined not only by the explosive mass but heavily by the degree of physical confinement (tamping), standoff distance, atmospheric pressure, reflection of shock waves off walls, and structural shielding in the surrounding environment.

Question 59

The most abundant elements in crude petroleum are

Accepted Answer

Option C: Carbon and Hydrogen. Crude petroleum is predominantly a complex mixture of hydrocarbon compounds. Carbon (83% to 87%) and Hydrogen (10% to 14%) together constitute over 95% to 99% of its total elemental mass.

Question 60

Which of the following is used to measure API gravity?

Accepted Answer

Option D: Density of crude oil. API gravity (American Petroleum Institute gravity) is a dimensionless measure of how heavy or light a petroleum liquid is compared to water, determined directly from the relative density / specific gravity of the oil at 60°F via the formula: API = (141.5 / SG) - 131.5.

Question 61

Fractional distillation of crude oil is based on differences in

Accepted Answer

Option C: Boiling point. Fractional distillation separates the complex hydrocarbon components of crude petroleum into commercial fractions (gasoline, kerosene, diesel, lubricating oil) based on differences in their boiling points.

Question 62

The flash point of diesel is generally

Accepted Answer

Option C: Higher than petrol. Petrol (gasoline) is highly volatile with a very low flash point of approximately -40°C to -43°C, whereas diesel fuel has a flash point of roughly +52°C to +65°C, making the flash point of diesel substantially higher than petrol.

Question 63

Seat of fire in an arson case determined the

Accepted Answer

Option A: Origin of fire. In fire and arson investigation, the 'seat of fire' is the precise physical point or area of origin where the fire initially started, characterized by the deepest charring, structural spalling, and low burn marks.

Question 64

Match the followings:
Flame Colour
I. Dark Red
II. White
III. Bright Yellow
IV. Orange
Temperature
a. 1400°C or above
b. 1200°C - 1400°C
c. 600°C - 800°C
d. 1000°C - 1200°C
Choose the correct answer from the options given below:

Accepted Answer

Option B: I - c, II - a, III - b, IV - d. In fire investigation color-temperature pyrometry: Dark Red corresponds to ~600°C - 800°C (c); Orange corresponds to ~1000°C - 1200°C (d); Bright Yellow corresponds to ~1200°C - 1400°C (b); White indicates extremely intense combustion at 1400°C or above (a). Thus, I-c, II-a, III-b, IV-d.

Assistant Scientific Officer (Chemistry and Toxicology)2026

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JKSSB — Assistant Scientific Officer (Chemistry and Toxicology) (2026)

The first Chemical Examiner's Laboratory in India was established in:

Arthashastra primarily emphasized forensic practices related to:

The Central Forensic Science Laboratory (CFSL), Kolkata was established in:

Which of the following tests was one of the first developed for Arsenic detection?

Locard's exchange principle implies all of the following except

Which of these is the best method for crime scenes without physical barriers?

Which of the following are commonly used tools in crime scene investigation?I. Tweezers and forcepsII. Magnifying lensIII. Evidence collection bagsIV. DNA sequencerChoose the correct answer from the options given below:

Which of the following search methods are useful if a single investigator is present at a crime scene?I. Grid patternII. Spiral patternIII. Zone patternIV. Linear patternChoose the correct answer from the options given below:

What is the first priority of a police officer at the crime scene?

Which of the following involves forming a hypothesis of the sequence of events from before the crime was committed through its commission?

Which of the following deals with the making of sketch of an outdoor crime scene with large area by selecting the focal point?

Informational evidence obtained from statements of persons who have some knowledge of the crime scene are called as -

Which of the following variable can assume any numerical value over a certain interval?

Which of the following methods use sample results to help make decisions or predictions about a population?

Which of the following distributions is used for hypothesis testing?

Which of the following scales shows equal intervals?I. Nominal scaleII. Ordinal scaleIII. Interval scaleIV. Ratio scaleChoose the correct answer from the options given below:

Which of the following test is useful to find analysis of variance in a sample data?

Which of the following represent degree of symmetry in statistical calculation

Which statement best reflects the judicial view of expert testimony?

The primary objective of cross-examining an expert witness is to:

Match the followings:List - II. BarbituratesII. MAO InhibitorsIII. LSDIV. CocaineList - IIa. Stimulantb. Depressantc. Anti-Depressantd. HallucinogenChoose the correct answer from the options given below:

When gelatin is mixed with a hallucinogen drug and cut into small squares, it is known as

Which of the followings are synthetic opioids?I. MorphineII. MethadoneIII. OxyContinIV. HeroinChoose the correct answer from the options given below:

Which of the following chemicals are precursors for methamphetamine synthesis?I. EphedrineII. SafroleIII. CaffeineIV. Phenyl-2-propanone (P2P)Choose the correct answer from the options given below:

According to SWGDRUG guidelines, which analytical technique is classified under Category A for the identification of controlled substances?

Which of the following drugs come under the schedule III of controlled substance act?

Which of the following plant poisons is commonly known as railroad poison?

Naloxone is the specific antidote used in poisoning due to

Which of the following is associated with sinsemilla?

Which of the following method adopted for the desirable effect of Khat?

Match the followings:Drug NameI. CannabisII. CocaineIII. AlcoholIV. BrucineConditiona. Magnan's symptomb. Opisthotonosc. Run Amokd. Delirium tremensChoose the correct answer from the options given below:

Which of the following is correct in Marquis test?I. Opium - Purple colourII. Amphetamine - orange brown colourIII. Opium - Orange colourIV. Amphetamine - bluish Purple colourChoose the correct answer from the options given below:

Which of the following is synthesized through amine displacement method using safrole as the precursor?

Match the followings:Drug NameI. BarbituratesII. BenzodiazepineIII. LSDIV. CocaineIdentification Testa. Ehrlich's testb. Scott testc. Dillie-Koppanyi testd. Zimmermann testChoose the correct answer from the options given below:

When phencyclidine is mixed with LSD, it is known as

A condition in which an individual inject amphetamine at every 2-3 hours is known as

Which of the following is a group of completely synthetic drugs?

Which of the following are naturally occurring drug?I. MarijuanaII. PsilocybinIII. PeyoteIV. LSDChoose the correct answer from the options given below:

Which of the following is an active principle of dhatura?

Match the followings:DrugsI. KetamineII. Gamma-Hydroxybutyric acidIII. RohypnolIV. MDMAStreet Namesa. Liquid Gb. Rollsc. Special Kd. CirclesChoose the correct answer from the options given below:

Which of the following is causing high psychological dependency but no physical dependency?

The hallucinogenic effects of LSD were first described by

Which of the following is a designer drug?

Which of the following presumptive test give dull orange colour with psilocobin?

Which of the following is a group of cardiac poison?

Which of the following is a combination of acid base drug?

Which of the following is used for the isolation of organic non-volatile substances?

Which of the following benzodiazepines have shortest half-life period?

Mescaline is obtained from which of the following

In which of the following class of the Explosive Act Rules, 1983, chlorate mixture is classified?

Which of the following is a tertiary explosive?

Which of the following is used in percussion cap of firearm ammunition?I. FulminatesII. Lead AzideIII. Lead StyphnateIV. DinolChoose the correct answer from the options given below:

Match the followings:List - I Name of ExplosiveI. CyclotolII. PentoliteIII. TerytolIV. OctolList - II Compositiona. HMX + TNTb. RDX + TNTc. PETN + TNTd. TNT + TetrylChoose the correct answer from the options given below:

Why is it difficult to estimate the quantity of explosive used based solely on damage?

The most abundant elements in crude petroleum are

Which of the following is used to measure API gravity?

Fractional distillation of crude oil is based on differences in

The flash point of diesel is generally

Seat of fire in an arson case determined the

Match the followings:Flame ColourI. Dark RedII. WhiteIII. Bright YellowIV. OrangeTemperaturea. 1400°C or aboveb. 1200°C - 1400°Cc. 600°C - 800°Cd. 1000°C - 1200°CChoose the correct answer from the options given below:

Which of the following occurs when the density of liquids and gases is reduced, causing them to expand and rise on heat transfer?

Where is the fire's greatest damage?

Which of the following enzyme present in saliva to breaks down carbohydrates?

Peptide bonds are formed between:

Which of the following are reducing sugars?I. GlucoseII. SucroseIII. MaltoseIV. LactoseChoose the correct answer from the options given below:

Match the followings:List-I (Enzymes)I. AmylaseII. PepsinIII. LipaseIV. TrypsinList-II (Functions)a. Protein digestionb. Starch digestionc. Fat digestiond. Peptide digestionChoose the correct answer from the options given below:

Essential amino acids include:I. ValineII. LeucineIII. GlycineIV. LysineChoose the correct answer from the options given below:

Bones are preserved in case of poisoning due to the

What is the fatal dose of strychnine?

What is the fatal dose of bhang?

QuEChERS method is suitable for:I. Pesticides in foodII. Drugs in biological fluidsIII. Environmental pollutantsIV. Metals in solid samplesChoose the correct answer from the options given below:

HPLC is preferred over GC when analytes are:

In which test is alcohol burned with oxygen in the air to determine the quantity of alcohol?

Why are window glass patterns important in post-blast reconstruction?

Adjusting sample pH prior to SPE is essential primarily to:

Why is retention time alone insufficient for qualitative identification?

Matrix effects primarily compromise quantitative analysis by:

Which of the following are commonly used tools in crime scene investigation?
I. Tweezers and forceps
II. Magnifying lens
III. Evidence collection bags
IV. DNA sequencer
Choose the correct answer from the options given below:

Which of the following search methods are useful if a single investigator is present at a crime scene?
I. Grid pattern
II. Spiral pattern
III. Zone pattern
IV. Linear pattern
Choose the correct answer from the options given below:

Which of the following scales shows equal intervals?
I. Nominal scale
II. Ordinal scale
III. Interval scale
IV. Ratio scale
Choose the correct answer from the options given below:

Match the followings:
List - I
I. Barbiturates
II. MAO Inhibitors
III. LSD
IV. Cocaine
List - II
a. Stimulant
b. Depressant
c. Anti-Depressant
d. Hallucinogen
Choose the correct answer from the options given below:

Which of the followings are synthetic opioids?
I. Morphine
II. Methadone
III. OxyContin
IV. Heroin
Choose the correct answer from the options given below:

Which of the following chemicals are precursors for methamphetamine synthesis?
I. Ephedrine
II. Safrole
III. Caffeine
IV. Phenyl-2-propanone (P2P)
Choose the correct answer from the options given below:

Match the followings:
Drug Name
I. Cannabis
II. Cocaine
III. Alcohol
IV. Brucine
Condition
a. Magnan's symptom
b. Opisthotonos
c. Run Amok
d. Delirium tremens
Choose the correct answer from the options given below:

Which of the following is correct in Marquis test?
I. Opium - Purple colour
II. Amphetamine - orange brown colour
III. Opium - Orange colour
IV. Amphetamine - bluish Purple colour
Choose the correct answer from the options given below:

Match the followings:
Drug Name
I. Barbiturates
II. Benzodiazepine
III. LSD
IV. Cocaine
Identification Test
a. Ehrlich's test
b. Scott test
c. Dillie-Koppanyi test
d. Zimmermann test
Choose the correct answer from the options given below:

Which of the following are naturally occurring drug?
I. Marijuana
II. Psilocybin
III. Peyote
IV. LSD
Choose the correct answer from the options given below:

Match the followings:
Drugs
I. Ketamine
II. Gamma-Hydroxybutyric acid
III. Rohypnol
IV. MDMA
Street Names
a. Liquid G
b. Rolls
c. Special K
d. Circles
Choose the correct answer from the options given below:

Which of the following is used in percussion cap of firearm ammunition?
I. Fulminates
II. Lead Azide
III. Lead Styphnate
IV. Dinol
Choose the correct answer from the options given below:

Match the followings:
List - I Name of Explosive
I. Cyclotol
II. Pentolite
III. Terytol
IV. Octol
List - II Composition
a. HMX + TNT
b. RDX + TNT
c. PETN + TNT
d. TNT + Tetryl
Choose the correct answer from the options given below:

Match the followings:
Flame Colour
I. Dark Red
II. White
III. Bright Yellow
IV. Orange
Temperature
a. 1400°C or above
b. 1200°C - 1400°C
c. 600°C - 800°C
d. 1000°C - 1200°C
Choose the correct answer from the options given below:

Which of the following are reducing sugars?
I. Glucose
II. Sucrose
III. Maltose
IV. Lactose
Choose the correct answer from the options given below:

Match the followings:
List-I (Enzymes)
I. Amylase
II. Pepsin
III. Lipase
IV. Trypsin
List-II (Functions)
a. Protein digestion
b. Starch digestion
c. Fat digestion
d. Peptide digestion
Choose the correct answer from the options given below:

Essential amino acids include:
I. Valine
II. Leucine
III. Glycine
IV. Lysine
Choose the correct answer from the options given below:

QuEChERS method is suitable for:
I. Pesticides in food
II. Drugs in biological fluids
III. Environmental pollutants
IV. Metals in solid samples
Choose the correct answer from the options given below:

What are the poisons come under the category of Inebriant?
I. Dhatura
II. Ether
III. Chloroform
IV. Belladona
Choose the correct answer from the options given below:

Which of the following chelating agents used for the management of heavy metal poisoning?
I. EDTA
II. BAL
III. Starch
IV. Vinegar
Choose the correct answer from the options given below:

Which of the following are examples of hyphenated techniques?
I. GC
II. GC-MS
III. HPLC
IV. LC-MS
Choose the correct answer from the options given below: