datavorous/entrance-exam-dataset huggingface dataset:
Which process is used to make nitrates from carbonates?

Options:
A Dissolution in concentrated nitric acid
B Dissolution in dilute nitric acid
C Heating with concentrated nitric acid
D Heating with concentrated sulfuric acid

The correct answer is:
Dissolution in dilute nitric acid

Solution:
Nitrates are typically made by dissolving carbonates in dilute nitric acid, which is a common method to produce nitrates.

Topic: Chemistry, s Block Elements, NEET
Which process results in decrease of nitrogen content in soil?

Options:
A Ammonification
B Biological nitrogen fixation
C Denitrification
D Nitrification

The correct answer is:
Denitrification

Solution:
The bacteria which carry out denitrification are called denitrifying bacteria, like Thiobacillus denitrificans, Pseudomonas aeruginosa and Micrococcus denitrificans also occur in the soil which converts the nitrate and ammonia into atmospheric free elemental nitrogen. The process in which molecular nitrogen is released back into the atmosphere by reduction of nitrate present in the soil is called denitrification.

Topic: Biology, Mineral Nutrition, NEET
Which process utilizes finely divided iron as a catalyst?

Options:
A Contact Process
B Catalytic Hydrogenation
C Haber's Process
D Persulphate ion reaction

The correct answer is:
Haber's Process

Solution:
The transition metals and their compounds are known for their catalytic activity. This activity is ascribed to their ability to adopt multiple oxidation states and to form complexes. Vanadium(V) oxide (in Contact Process), finely divided iron (in Haber’s Process), and nickel (in Catalytic Hydrogenation) are some of the examples

Topic: Chemistry, d and f Block Elements, NEET
Which process utilizes iron catalysts for the production of ammonia?

Options:
A Haber process
B Wacker process
C Polymerization
D Sulfuric acid production

The correct answer is:
Haber process

Solution:
Iron catalysts are used in the Haber process for the production of ammonia.

Topic: Chemistry, d and f Block Elements, NEET
Which product is formed at the cathode during the Kolbe's electrolytic method?

Options:
A Alkane
B Carboxylic acid
C Hydroxide ion
D Methyl free radical

The correct answer is:
Hydroxide ion

Solution:
Hydroxide ions are formed at the cathode during Kolbe's electrolytic method.

Topic: Chemistry, Hydrocarbons, NEET
Which product is formed, when acetonitrile is hydrolysed partially with cold concentrated HCl?

Options:
A Methyl cyanide
B Acetic anhydride
C Acetic acid
D Acetamide

The correct answer is:
Acetamide

Solution:
CH3-C≡ΝAcetonitrile→conc.HClCH3-CO-NH2Acetamide

Topic: Chemistry, Amines, NEET
Which product is formed when O22-reacts with H2O?

Options:
A OH-
B O2
C O3
D O2-

The correct answer is:
OH-

Solution:
Correct Option is : (A)
OH-

Topic: Chemistry, s Block Elements, NEET
Which product is formed when the following compound is treated with Br2 in the presence of FeBr3?

Options:
A
B
C
D

The correct answer is:

Solution:
m-xylene on bromination with bromine in presence of ferric bromide gives 1-bromo-2,4-dimethylbenzene.
This is represented by option C which shows a pair of identical compounds.
This is an electrophilic aromatic substitution reaction and since the methyl group is ortho para directing, the substitution occurs at a position which is ortho to one methyl group and para to other methyl group.

Topic: Chemistry, Haloalkanes and Haloarenes, NEET, NEET 2014
Which product is formed when the following compound is treated with Br2 in the presence of FeBr3?

Options:
A
B
C
D

The correct answer is:

Solution:

Topic: Chemistry, Alcohols Phenols and Ethers, NEET
Which property characterizes non-metallic solids, according to the paragraph?

Options:
A Malleability
B Ductility
C Conductivity
D Brittleness

The correct answer is:
Brittleness

Solution:
The most non-metallic solids are brittle and are neither malleable nor ductile.

Topic: Chemistry, Classification of Elements and Periodicity in Properties, NEET
Which property contributes to the non-systematic trend in the melting and boiling points of certain metals compared to alkali metals?

Options:
A Atomic mass
B Atomic size
C Ionization energy
D Electronegativity

The correct answer is:
Atomic size

Solution:
The non-systematic trend in the melting and boiling points of certain metals compared to alkali metals is primarily due to differences in atomic size. Smaller-sized atoms tend to have higher melting and boiling points due to stronger metallic bonding.

Topic: Chemistry, s Block Elements, NEET
Which property in thermodynamics depends on the size of the container in which a substance is placed?

Options:
A Temperature
B Pressure
C Mass
D Density

The correct answer is:
Pressure

Solution:
Pressure is an intensive property that depends on the size of the container and the amount of matter present.

Topic: Chemistry, Thermodynamics (C), NEET
Which property is represented by the coefficient "c" in the equation q = c * m * ∆T?

Options:
A Heat capacity
B Mass
C Temperature change
D Specific heat

The correct answer is:
Specific heat

Solution:
The coefficient "c" in the equation represents specific heat, which is the quantity of heat required to raise the temperature of one unit mass of a substance by one degree Celsius (or one kelvin).

Topic: Chemistry, Thermodynamics (C), NEET
Which property of beryllium (Be) contributes to its weaker reducing nature?

Options:
A Large atomic radius.
B Low ionization energy.
C Small ionic radius.
D High electronegativity.

The correct answer is:
Small ionic radius.

Solution:
The small ionic radius of beryllium contributes to its weaker reducing nature.

Topic: Chemistry, s Block Elements, NEET
Which property of phenols allows them to be soluble in water?

Options:
A Presence of aromatic rings
B Hydrophobic alkyl groups
C Formation of hydrogen bonds with water
D High molecular mass

The correct answer is:
Formation of hydrogen bonds with water

Solution:
Phenols can form hydrogen bonds with water molecules due to the -OH group.

Topic: Chemistry, Alcohols Phenols and Ethers, NEET
Which property of the alkaline earth metals increases as you move down the group from beryllium to barium?

Options:
A Melting points
B Electronegativity
C Electropositive character
D Ionization energy

The correct answer is:
Electropositive character

Solution:
The electropositive character of the alkaline earth metals increases as you move down the group from beryllium to barium.

Topic: Chemistry, s Block Elements, NEET
Which property of water makes it have a strong hydrating tendency and allows it to dissolve many ionic compounds?

Options:
A High dielectric constant
B Low density
C High boiling point
D Low heat capacity

The correct answer is:
High dielectric constant

Solution:
Water's high dielectric constant gives it a strong hydrating tendency and allows it to dissolve many ionic compounds.

Topic: Chemistry, Hydrogen, NEET
Which protective devices are workers involved in waste disposal often lacking?

Options:
A Helmets and safety vests.
B Gloves, water-proof boots, and gas masks.
C Earplugs and safety goggles.
D Dust masks and hard hats.

The correct answer is:
Gloves, water-proof boots, and gas masks.

Solution:
Workers involved in waste disposal often lack protective devices such as gloves, water-proof boots, and gas masks.

Topic: Chemistry, Environmental Chemistry, NEET
Which protein is commonly found in hair, wool, and silk and is an example of a fibrous protein?

Options:
A Insulin
B Myosin
C Albumin
D Keratin

The correct answer is:
Keratin

Solution:
Keratin is a common example of a fibrous protein found in hair, wool, and silk.

Topic: Chemistry, Biomolecules, NEET
Which purification technique is based on the selective solubility of a compound in different solvents?

Options:
A Sublimation
B Crystallisation
C Distillation
D Differential extraction

The correct answer is:
Differential extraction

Solution:
Differential extraction is based on the selective solubility of a compound in different solvents.

Topic: Chemistry, General Organic Chemistry, NEET
Which purification technique is specifically effective for compounds that sublime?

Options:
A Crystallization
B Distillation
C Sublimation
D Chromatography

The correct answer is:
Sublimation

Solution:
Sublimation is specifically effective for compounds that sublime, i.e., change directly from solid to vapor when heated.

Topic: Chemistry, General Organic Chemistry, NEET
Which purification technique relies on the principle that different compounds have different boiling points?

Options:
A Sublimation
B Crystallisation
C Distillation
D Differential extraction

The correct answer is:
Distillation

Solution:
Distillation relies on the principle that different compounds have different boiling points, allowing them to be separated.

Topic: Chemistry, General Organic Chemistry, NEET
Which quantity out of ∆rG and ∆rG⊖will be zero at equilibrium?

Options:
A ∆rG will always be zero and ∆rG⊖is zero for K = 10 because ∆G⊖= – RT lnK
B ∆rG will always be zero and ∆rG⊖is zero for K = 0 because ∆G⊖= – RT lnK
C ∆rG will always be non-zero and ∆rG⊖is zero for K = 1 because ∆G⊖= – RT lnK
D ∆rG will always be zero and ∆rG⊖is zero for K = 1 because ∆G⊖= – RT lnK

The correct answer is:
∆rG will always be zero and ∆rG⊖is zero for K = 1 because ∆G⊖= – RT lnK

Solution:
Correct Option is : (D)
∆rG will always be zero and ∆rG⊖is zero for K = 1 because ∆G⊖= – RT lnK

Topic: Chemistry, Thermodynamics (C), NEET
Which quantum number determines the subshell and the shape of the orbital?

Options:
A n
B l
C ml
D ms

The correct answer is:
l

Solution:
The quantum number 'l' identifies the subshell and determines the shape of the orbital.

Topic: Chemistry, Structure of Atom, NEET
Which quantum number identifies the shell and determines the size and energy of the orbital?

Options:
A n
B l
C ml
D ms

The correct answer is:
n

Solution:
The quantum number 'n' identifies the shell, determines the size of the orbital, and to a large extent, the energy of the orbital.

Topic: Chemistry, Structure of Atom, NEET
Which quantum numbers define an orbital in the s subshell of the third shell?

Options:
A n = 1, l = 0, ml = 0
B n = 2, l = 0, ml = 0
C n = 3, l = 0, ml = 0
D n = 3, l = 1, ml = 0

The correct answer is:
n = 3, l = 0, ml = 0

Solution:
An orbital in the s subshell of the third shell is defined by the quantum numbers n = 3, l = 0, and ml = 0.

Topic: Chemistry, Structure of Atom, NEET
Which reactant is the limiting reagent in the reaction 2A + 4B → 3C + 4D when 5 moles of A react with 6 moles of B?

Options:
A A
B B
C C
D D

The correct answer is:
B

Solution:
Correct Option is : (B)
B

Topic: Chemistry, Some Basic Concepts of Chemistry, NEET
Which reaction converts acid chlorides into carboxylic acids more readily?

Options:
A Hydrolysis with water
B Hydrolysis with aqueous base
C Oxidation with oxygen
D Reduction with hydrogen

The correct answer is:
Hydrolysis with aqueous base

Solution:
Acid chlorides can be more readily converted into carboxylic acids by hydrolysis with aqueous base.

Topic: Chemistry, Aldehydes, Ketones and Carboxylic Acids, NEET
Which reaction does hydroquinone undergo most readily?

Options:
A SN2 subbstitution
B Hydrolysis
C Oxidation
D Reduction

The correct answer is:
Oxidation

Solution:
Oxidation reaction is undergone by hydroquinone most readily.

Topic: Chemistry, Hydrocarbons, NEET
Which reaction gives colloidal solution

Options:
A Cu+HgCl2→CuCl2+Hg
B 2HNO3+3H2S→3S+4H2O+2NO
C 2Mg+CO2→2MgO+C
D Cu+CuCl2→Cu2Cl2

The correct answer is:
2HNO3+3H2S→3S+4H2O+2NO

Solution:
2HNO3+3H2S→3S+4H2O+2NO , this is used to obtain colloidal sulphur.

Topic: Chemistry, Surface Chemistry, NEET
Which reaction is NOT a redox reaction?

Options:
A $2 \mathrm{KClO}_3+\mathrm{I}_2 \rightarrow 2 \mathrm{KIO}_3+\mathrm{Cl}_2$
B $\mathrm{H}_2+\mathrm{Cl}_2 \rightarrow 2 \mathrm{HCl}$
C $\mathrm{BaCl}_2+\mathrm{Na}_2 \mathrm{SO}_4 \rightarrow \mathrm{BaSO}_4+2 \mathrm{NaCl}$
D $\mathrm{Zn}+\mathrm{CuSO}_4 \rightarrow \mathrm{ZnSO}_4+\mathrm{Cu}$

The correct answer is:
$\mathrm{BaCl}_2+\mathrm{Na}_2 \mathrm{SO}_4 \rightarrow \mathrm{BaSO}_4+2 \mathrm{NaCl}$

Solution:
(3) $\mathrm{BaCl}_2^{-1}+\mathrm{Na}_2^{+1} \mathrm{SO}_4^{-2} \longrightarrow \stackrel{+2}{\mathrm{BaSO}_4+2 \mathrm{NaCl}^{-1}}$
This is not a redox reaction as there is no change in oxidation state.

Topic: Chemistry, Redox Reactions, NEET, NEET 2024
Which reaction is not feasible?

Options:
A $2 \mathrm{KI}+\mathrm{Br}_2 \rightarrow 2 \mathrm{KBr}+\mathrm{I}_2$
B $2 \mathrm{KBr}+\mathrm{I}_2 \rightarrow 2 \mathrm{KI}+\mathrm{Br}_2$
C $2 \mathrm{KBr}+\mathrm{Cl}_2 \rightarrow 2 \mathrm{KCl}+\mathrm{Br}_2$
D $2 \mathrm{H}_2 \mathrm{O}+2 \mathrm{~F}_2 \rightarrow 4 \mathrm{HF}+\mathrm{O}_2$

The correct answer is:
$2 \mathrm{KBr}+\mathrm{I}_2 \rightarrow 2 \mathrm{KI}+\mathrm{Br}_2$

Solution:
$2 \mathrm{KBr}+\mathrm{I}_2 \rightarrow 2 \mathrm{KI}+\mathrm{Br}_2$ reaction is not possible because $\mathrm{Br}^{-}$ion is not oxidised in $\mathrm{Br}_2$ with $\mathrm{I}_2$ due to higher electrode (oxidation) potential of $\mathrm{I}_2$ than bromine.
Energetically favorable means no energy input needed for reaction to take place.

Topic: Chemistry, Electrochemistry, NEET, NEET 2002
Which reaction is preferred at the anode for higher concentrations of sulfuric acid (H2SO4)?

Options:
A 2H2O(l) → O2(g) + 4H+(aq) + 4e-
B 2SO (aq) → S2O82- (aq) + 2e-
C 2H2(l) → O2(g) + 4H+(aq) + 4e-
D 2SO42- (aq) → S2O82- (aq) + 2e-

The correct answer is:
2SO42- (aq) → S2O82- (aq) + 2e-

Solution:
For higher concentrations of sulfuric acid (H2SO4), the preferred reaction at the anode is 2SO42- (aq) → S2O82- (aq) + 2e-.

Topic: Chemistry, Electrochemistry, NEET
Which reaction is responsible for the conversion of an alkene to an alkane by adding hydrogen atoms?

Options:
A Halogenation
B Hydration
C Dehydration
D Hydrogenation

The correct answer is:
Hydrogenation

Solution:
Hydrogenation is the process of adding hydrogen atoms to an alkene, converting it into an alkane.

Topic: Chemistry, Biomolecules, NEET
Which reaction is suitable for preparing α -Chloroacetic acid?

Options:
A Hell-Volhard-Zelinsky reaction
B Stephen's reaction
C Perkin's reaction
D None of these

The correct answer is:
Hell-Volhard-Zelinsky reaction

Solution:
HVZ reaction is the halogenation of carboxylic acid with alpha hydrogen by red P and X2.

Topic: Chemistry, Carboxylic Acid Derivatives, NEET
Which reaction pathway is involved in the reduction of phenol to benzene with zinc dust?

Options:
A Oxidation
B Hydrolysis
C Dehydration
D Reduction

The correct answer is:
Reduction

Solution:
The reduction of phenol to benzene involves a reduction reaction, where oxygen atoms are removed from the phenol molecule.

Topic: Chemistry, Hydrocarbons, NEET
Which reaction represents the addition of hydrogen to a substance?

Options:
A 2 FeCl3 (aq) + H2 (g) → 2 FeCl2 (aq) + 2 HCl(aq)
B 2 HgO (s) 2 Hg (l) + O2 (g)
C CH2 = CH2 (g) + H2 (g) → H3C – CH3 (g)
D 2HgCl2 (aq) + SnCl2 (aq) → Hg2Cl2 (s)+SnCl4 (aq)

The correct answer is:
CH2 = CH2 (g) + H2 (g) → H3C – CH3 (g)

Solution:
The reaction involving the addition of hydrogen to a substance is CH2 = CH2 (g) + H2 (g) → H3C – CH3 (g)

Topic: Chemistry, Redox Reactions, NEET
Which reagent can also be used for the reduction of nitriles to primary amines besides LiAlH4?

Options:
A Sodium (Na)
B Hydrochloric acid (HCl)
C Sodium borohydride (NaBH4)
D Sodium cyanide (NaCN)

The correct answer is:
Sodium borohydride (NaBH4)

Solution:
Besides LiAlH4, sodium borohydride (NaBH4) can also be used for the reduction of nitriles to primary amines.

Topic: Chemistry, Amines, NEET
Which reagent can be used to oxidise CH 3 CH = CHCHO into CH 3 CH = CHCOOH ?

Options:
A Selenium dioxide
B MnO 2
C Alkaline Tollen's reagent
D All of these

The correct answer is:
Alkaline Tollen's reagent

Solution:
Tollen’s reagent oxidises aldehyde to carboxylic acid without affecting carbon carbon multiple bond
CH3CH=CHCHO+2[Ag(NH3)2]+→2Ag+4NH3+CH3CH=CHCOOH+H2O

Topic: Chemistry, Aldehydes and Ketones, NEET
Which reagent can be used to oxidised aldehydes

Options:
A Tollen's reagent
B Fehling solution
C Benedict solution
D All of these

The correct answer is:
All of these

Solution:
All test for Aldehyde because ketone require strong oxidising agent.
2[Ag(NH3)2]++RCHO→RCOOH+2Ag+4NH3+H2O

Topic: Chemistry, Aldehydes and Ketones, NEET
Which reagent can convert acetic acid into ethanol?

Options:
A Na + alcohol
B LiAlH4 + ether
C H2+Pt
D Sn+HCl

The correct answer is:
LiAlH4 + ether

Solution:
LiAlH4+ ether, is reducing agent.
It reduce all types of carboxylic acids to alcohols. So, this reagent can be use to convert acetic acid into ethanol. CH 3 COOH â LiAlH 4 /ether CH 3 CH 2 OH

Topic: Chemistry, Alcohols Phenols and Ethers, NEET
Which reagent can forms crystalline osazone derivative with glucose?

Options:
A Fehling solution
B Phenylhydrazine
C Benedict solution
D Hydroxylamine

The correct answer is:
Phenylhydrazine

Solution:

Topic: Chemistry, Biomolecules, NEET
Which reagent gives pink colour with aldehyde?

Options:
A Tollen's reagent
B Schiff reagent
C Fehling solution
D Benedict solution

The correct answer is:
Schiff reagent

Solution:
Schiff's reagent Pink → SO 2 colourless → Aldehyde pink colour

Topic: Chemistry, Aldehydes and Ketones, NEET
Which reagent is commonly used for the dehydrohalogenation of vicinal dihalides to form alkenes?

Options:
A Hydrochloric acid
B Sodium hydroxide
C Sodamide
D Oxygen

The correct answer is:
Sodamide

Solution:
Sodamide is commonly used for the dehydrohalogenation of vicinal dihalides to form alkenes.

Topic: Chemistry, Hydrocarbons, NEET
Which reagent is commonly used for the oxidation of primary alcohols to carboxylic acids in acidic media?

Options:
A Potassium permanganate (KMnO4)
B Potassium dichromate (K2Cr2O7)
C Chromium trioxide (CrO3)
D Jones reagent

The correct answer is:
Jones reagent

Solution:
Jones reagent is commonly used for the oxidation of primary alcohols to carboxylic acids in acidic media.

Topic: Chemistry, Aldehydes, Ketones and Carboxylic Acids, NEET
Which reagent is responsible for giving an intense blue color with starch in the method of Iodometry?

Options:
A Cu2+(aq)
B I2(aq)
C S2O32- ions
D KI

The correct answer is:
I2(aq)

Solution:
Iodine (I2) gives an intense blue color with starch in the method described.

Topic: Chemistry, Redox Reactions, NEET
Which reagent is responsible for introducing structural changes in the alkanes during the isomerization reaction?

Options:
A Hydrogen gas (H2)
B Hydrogen chloride gas (HCl)
C Anhydrous aluminum chloride (AlCl3)
D Oxygen gas (O2)

The correct answer is:
Hydrogen chloride gas (HCl)

Solution:
Hydrogen chloride gas is responsible for introducing structural changes in the alkanes by promoting isomerization. It initiates the rearrangement of carbon atoms in the alkane molecules.

Topic: Chemistry, Hydrocarbons, NEET
Which reagent is used for the haloform reaction to oxidize methyl ketones?

Options:
A Sodium hypochlorite
B Sodium hypobromite
C Sodium iodide
D Sodium cyanide

The correct answer is:
Sodium hypobromite

Solution:
The haloform reaction to oxidize methyl ketones typically uses sodium hypobromite as the reagent.

Topic: Chemistry, Aldehydes, Ketones and Carboxylic Acids, NEET
Which reagent is used to cleave the ozonide formed in the ozonolysis of alkenes?

Options:
A Zn-H2O
B HCl
C NaOH
D H2SO4

The correct answer is:
Zn-H2O

Solution:
The cleavage of the ozonide formed in ozonolysis of alkenes is typically achieved using Zn-H2O (zinc in the presence of water).

Topic: Chemistry, Hydrocarbons, NEET
Which reagent is used to convert the alkene formed from vicinal dihalides into an alkyne?

Options:
A Sulfuric acid
B Sodamide
C Potassium hydroxide
D Hydrochloric acid

The correct answer is:
Sodamide

Solution:
Sodamide is used to convert the alkene formed from vicinal dihalides into an alkyne.

Topic: Chemistry, Hydrocarbons, NEET
Which reagent is used to differenciate between aldehyde and ketone?

Options:
A Fehling's solution
B Tollen's reagent
C Schiff's reagent
D All of these

The correct answer is:
All of these

Solution:
Fehling solution is Alkaline CuSO4+Na-K tartarate
Tollen’s reagent is NH4OH+AgNO3
Schiff’s reagent is p-rosaniline hydrochloride or magneta
All these reagents are used to distinguish between aldehydes and ketones. Aldehydes reacts with all these reagents while ketones do not react.

Topic: Chemistry, Aldehydes and Ketones, NEET
Which reagent is used to distinguish between formaldehyde and acetaldehyde

Options:
A Tollen's reagent
B Fehling's Solution
C Schiff's reagent
D Caustic soda Solution

The correct answer is:
Caustic soda Solution

Solution:
2HCHO→NaOHCH3OH+HCOONa
It is a Cannizzaro’s reaction.
It is aldol condensation reaction.

Topic: Chemistry, Aldehydes and Ketones, NEET
Which reagent is used to initiate the reduction of nitro compounds with iron scrap and hydrochloric acid?

Options:
A Sodium hydroxide (NaOH)
B Hydrochloric acid (HCl)
C Water (H2O)
D Sodium borohydride (NaBH4)

The correct answer is:
Hydrochloric acid (HCl)

Solution:
Hydrochloric acid is used to initiate the reaction.

Topic: Chemistry, Amines, NEET
Which reagent primarily facilitates the rearrangement of carbon atoms in the isomerization reaction?

Options:
A Anhydrous aluminum chloride (AlCl3)
B Hydrogen chloride gas (HCl)
C Hydrogen gas (H2)
D Oxygen gas (O2)

The correct answer is:
Hydrogen chloride gas (HCl)

Solution:
Hydrogen chloride gas primarily facilitates the rearrangement of carbon atoms in the isomerization reaction, leading to the formation of branched-chain alkanes.

Topic: Chemistry, Hydrocarbons, NEET
Which reagent selectively reduces nitriles to imines in an alternative method?

Options:
A Stannous chloride
B Hydrochloric acid
C Diisobutylaluminium hydride (DIBAL-H)
D Aldehyde

The correct answer is:
Diisobutylaluminium hydride (DIBAL-H)

Solution:
Nitriles can be selectively reduced to imines using diisobutylaluminium hydride (DIBAL-H) in an alternative method.

Topic: Chemistry, Aldehydes, Ketones and Carboxylic Acids, NEET
Which reagent used to test unsaturation of alkenes?

Options:
A conc. H2SO4
B Solution of Br2 in CCl4
C Ammonical Cu2Cl2
D Ammonical AgNO3

The correct answer is:
Solution of Br2 in CCl4

Solution:
Solution of bromine in carbon tetrachloride is used to test for unsaturation of alkene. The reddish brown colour of bromine disappears due to the formation of colourless dibromo ethane (C2H4Br2) .

Topic: Chemistry, Hydrocarbons, NEET
Which reagents are NOT typically used to oxidize alkylbenzenes to aromatic carboxylic acids?

Options:
A Chromic acid
B Potassium permanganate
C Hydrochloric acid
D Chromium trioxide

The correct answer is:
Hydrochloric acid

Solution:
Hydrochloric acid is not typically used as an oxidizing agent to convert alkylbenzenes to aromatic carboxylic acids.

Topic: Chemistry, Aldehydes, Ketones and Carboxylic Acids, NEET
Which reduction method involves the treatment of aldehydes and ketones with hydrazine followed by heating with sodium or potassium hydroxide in a high-boiling solvent?

Options:
A Clemmensen reduction
B Wolff-Kishner reduction
C Sodium borohydride reduction
D Lithium aluminium hydride reduction

The correct answer is:
Wolff-Kishner reduction

Solution:
The reduction method that involves the treatment of aldehydes and ketones with hydrazine followed by heating with sodium or potassium hydroxide in a high-boiling solvent is known as Wolff-Kishner reduction.

Topic: Chemistry, Aldehydes, Ketones and Carboxylic Acids, NEET
Which reduction reaction occurs at the cathode during the electrolysis of sodium chloride solution?

Options:
A Na+ (aq) + e- → Na (s)
B H2O(aq) + e- → ½ H2(g)
C H2O (l ) + e- → ½H2(g) + OH-(aq)
D Cl- (aq) → ½ Cl2(g) + e-

The correct answer is:
H2O (l ) + e- → ½H2(g) + OH-(aq)

Solution:
At the cathode there is competition between the following reduction reactions:Na+ (aq) + e- → Na (s) (Eo cell = – 2.71 V)H+(aq) + e- → ½ H2(g)(Eo cell= 0.00 V) The reaction with higher value of Eo is preferred and therefore, the reaction at the cathode during electrolysis is: H+ (aq) + e- → ½ H2 (g) ( but H+ (aq) is produced by the dissociation of H2O), i.e., H2O (l ) → H+ (aq) + OH- (aq).

Topic: Chemistry, Electrochemistry, NEET