CBSE Class 12 Chemistry 2026
288 questions · 553 marks · every one with the board’s own marking-scheme answer.
What 2026 actually asked, chapter by chapter
Marks we counted in the 2026 papers themselves. CBSE allocates marks per unit, not per chapter — this is what was observed, not an official CBSE weightage.
| Chapter | Marks | Share |
|---|---|---|
| Biomolecules41 questions | 73 | 13.2% |
| Coordination Compounds32 questions | 64 | 11.6% |
| Amines40 questions | 60 | 10.8% |
| Electrochemistry22 questions | 58 | 10.5% |
| The d-and f-Block Elements31 questions | 56 | 10.1% |
| Chemical Kinetics30 questions | 51 | 9.2% |
| Solutions26 questions | 51 | 9.2% |
| Haloalkanes and Haloarenes24 questions | 51 | 9.2% |
| Aldehydes, Ketones and Carboxylic Acids16 questions | 48 | 8.7% |
| Alcohols, Phenols and Ethers26 questions | 41 | 7.4% |
All 288 questions from 2026
- Q1Which of the following curve represents the first order reaction?1 mkasked 3×
- Q1Which of the following will be the least reactive towards nucleophilic substitution reaction?1 mk
- Q1Which of the following is not correct for S N 1 reaction?1 mk
- Q1Consider the following reaction: Zn (s)+Ag 2 O (s)+H 2 O(l) → Zn (aq)^2++2 Ag (s)+2 OH (aq)^- Given: E^0 Ag^+ / Ag=0.80…1 mkasked 3×
- Q1Identify the correct statement:1 mk
- Q1In the ring structure of fructose, the anomeric carbon is1 mk
- Q1The mole fraction of a solute in 2.0 molal aqueous solution is:1 mkasked 3×
- Q1Which of the reactions is used in the conversion of a ketone into hydrocarbon?1 mkasked 3×
- Q1Which of the following is most basic?1 mk
- Q1Oxidation of chloroform by air in the presence of sunlight produces a poisonous gas known as:1 mk
- Q1Which property of transition metals enables them to form alloys?1 mk
- Q2Which of the following is the correct expression of K f which depends upon the nature of solvent?1 mk
- Q2Which of the following solutions will have the lowest freezing point in water?1 mk
- Q2Which of the following d-orbitals experience more repulsion in the crystal field splitting of tetrahedral complex?1 mk
- Q2Identify the correct statement:1 mkasked 2×
- Q2Lucas reagent produces cloudiness immediately with:1 mk
- Q2Dehydration of tertiary alcohols with Cu at 573 K gives:1 mk
- Q2The oxidation number of Pt in [Pt(en) 2 Cl 2]^2+ is:1 mk
- Q2The intermediate formed during the slowest step involved in the dehydration of alcohol is:1 mk
- Q3Which of the following solutions will have the highest osmotic pressure?1 mk
- Q3The coordination number of Co in [Co(en) 2 Cl 2]^+ is:1 mk
- Q3Which of the following, compounds is most reactive towards nucleophilic substitution reaction with aqueous NaOH?1 mk
- Q3The position of - Br in the compound can be classified as:1 mk
- Q3Which of the following product is formed when salicylic acid is treated with (CH 3 CO) 2 O in the presence of acid?1 mk
- Q3The oxidation number of Co in [Co(en) 3] 2(SO 4) 3 is:1 mk
- Q3The order for the given reaction is: A + 2B → Products Rate =k[A]^1 / 2[ B]^11 mkasked 3×
- Q3Which of the following d-orbitals experience more repulsion in the crystal field splitting of octahedral complex?1 mkasked 2×
- Q3Which of the following transition metals has lowest enthalpy of atomisation?1 mk
- Q3Electronic configuration of chromium is:1 mk
- Q3The major product of carbylamine reaction is:1 mkasked 3×
- Q3Which of the following is not a transition metal?1 mk
- Q4The chelating ligand used for the treatment of lead poisoning is:1 mk
- Q4Williamson synthesis is an example of:1 mk
- Q4Which of the following reagents are used to prepare primary amines by Hoffmann bromamide degradation reaction? (i) R- O…1 mkasked 3×
- Q4Which of the following represents the fraction of molecules with energies equal to or greater than E a?1 mk
- Q4For a reaction: N 2+3 H 2 → 2 NH 3, the rate of reaction with respect to NH 3 is1 mk
- Q4Electronic configuration of chromium is:1 mkasked 2×
- Q4The dehydration of 1°, 2° and 3° alcohols follows the order:1 mk
- Q4Actinoids show larger number of oxidation states:1 mkasked 3×
- Q4According to Werner's theory, the primary valencies of the central metal atom:1 mkasked 3×
- Q4Which reagent is used to distinguish between primary, secondary and tertiary amines?1 mk
- Q5How many Faradays are required to reduce 1 mol of Cr 2 O 7^2- to Cr^3+ in acidic medium?1 mk
- Q5Number of possible stereoisomers for the complex [Co(en) 2 Cl 2] Cl will be:1 mk
- Q5Consider the following reaction and identify A and B: CH 3 Cl+NaI dry acetone A+B1 mkasked 3×
- Q5Manganate ion is paramagnetic due to the presence of:1 mk
- Q5The oxidation number of Co in [Co(NH 3) 5(ONO)] SO 4 is:1 mk
- Q5The correct IUPAC name of the complex [Pt(NH 3) 2 C l 2] is:1 mkasked 3×
- Q5Which of the following reagent is used to distinguish between (C 2 H 5) 2 NH and (C 2 H 5) 3 N?1 mk
- Q5What will happen during the electrolysis of aqueous solution of CuCl 2 by using platinum electrodes?1 mk
- Q5Which of the following transition metals shows +1 and +2 oxidation states?1 mk
- Q6Which of the following Grignard Reagent will be used to prepare when treated with methanal?1 mk
- Q6Aspirin is obtained by acetylation of1 mk
- Q6The correct formula of Hinsberg's reagent is:1 mkasked 3×
- Q6Which of the following is heteroleptic complex?1 mkasked 3×
- Q6The correct order of decreasing basic strength in aqueous solution of the following is:1 mk
- Q6The correct order of decreasing basic strength of CH 3-NH 2,(CH 3) 2 NH and (CH 3) 3 N in aqueous solution is:1 mk
- Q6The correct order of decreasing basicities of C 2 H 5 NH 2,(C 2 H 5) 2 NH and (C 2 H 5) 3 N in aqueous solution is:1 mk
- Q7The secondary valency of Co in [Co(en) 3]^3+ is1 mk
- Q7The boiling point of one molal NaCl solution, assuming NaCl to be completely dissociated in water is: (K b. for…1 mkasked 3×
- Q7Which of the following molecules is chiral in nature?1 mkasked 3×
- Q7The correct order of decreasing order of pK b values is:1 mk
- Q7Which reagent is used to distinguish between C 2 H 5 NH 2 and (C 2 H 5) 2 NH?1 mk
- Q7The secondary valency of Pt in [Pt(en) 2 Cl 2]^2+ is1 mk
- Q7The secondary valency of Co in the complex [Co(NH 3) 5(NO 2)]^2+ is1 mk
- Q7In aqueous solution, Cr 2 O 7^2- ion converts to which of the following in alkaline medium?1 mk
- Q7Half-life (t 1 / 2) of a first order reaction is 1386 s. The value of rate constant is:1 mkasked 3×
- Q8When a liquid and its vapour are at equilibrium and the pressure is suddenly decreased:1 mkasked 3×
- Q8Which of the following ligands forms a chelate complex?1 mkasked 3×
- Q8At low temperature, phenol on reaction with Br 2 in CS 2 gives1 mk
- Q8(CH 3) 3 C-OC 2 H 5 on reaction with HI gives1 mk
- Q8Among the following, which one has the lowest value of pK b?1 mk
- Q8Which of the following transition metals shows +1 and +2 oxidation states?1 mkasked 2×
- Q8The boiling point of an azeotropic mixture of water and ethanol is less than that of pure water and ethanol. The…1 mk
- Q8At low temperature, phenol reacts with dil. HNO 3 to yield1 mk
- Q8Identify the correct increasing order of boiling points of the given compounds:1 mkasked 3×
- Q9Identify the compound produced by the reduction of Ethanenitrile with Lithium aluminium hydride:1 mkasked 3×
- Q9Consider the following cell at 298 K: Mg(s) Mg^2+(1 · 0 M) Cu^2+(1 · 0 M) Cu(s) How can we increase the emf of the cell…1 mkasked 3×
- Q9On hydrolysis, which of the following carbohydrates gives only β -glucose?1 mk
- Q9In aqueous acidified solution, CrO 4^2- ion converts to which of the following?1 mk
- Q9Which of the following is 'not' true about enantiomers?1 mkasked 3×
- Q9How the conductivity varies on decreasing concentration for both weak and strong electrolytes?1 mk
- Q9Primary, secondary and tertiary alcohols can be distinguished by:1 mkasked 3×
- Q10CH 3-NH 2 on reaction with (CH 3 CO) 2 O gives1 mk
- Q10The rate of a first order reaction is 5 · 6 × 10^-4 mol L^-1 s^-1, when the concentration of reactant is 0.2 mol L^-1.…1 mkasked 3×
- Q10Each polypeptide in a protein has amino acids linked with each other in a specific sequence and it is this sequence of…1 mk
- Q10Aniline on direct nitration yields1 mkasked 3×
- Q10Consider the following compounds: Chlorobenzene (I), 2,4,6-trinitrochlorobenzene (II), 2,4-dinitrochlorobenzene (III),…1 mk
- Q10Consider the following compounds: C 2 H 5 NH 2,(C 2 H 5) 2 NH, C 6 H 5 CH 2 NH 2, NH 3, C 6 H 5 NH 2 The correct…1 mkasked 3×
- Q10The base which is present in DNA but not in RNA is:1 mkasked 3×
- Q10On electrolysis of very dilute aqueous solution of NaCl using platinum electrodes:1 mkasked 3×
- Q10The boiling point of an azeotropic mixture of water and nitric acid is more than that of pure water and nitric acid.…1 mk
- Q11The activation energy of a reaction can be determined from the slope of which of the following curves?1 mk
- Q11Identify the polysaccharide among the following:1 mkasked 3×
- Q11Nucleic acids are polymers of:1 mk
- Q11Which of the following reagent is used to convert benzene diazonium chloride to benzene?1 mk
- Q11Which of the following amines has lowest pK b value?1 mk
- Q11On hydrolysis, which of the following carbohydrates gives only glucose?1 mk
- Q11An example of non-reducing sugar is1 mk
- Q11Proteins are polymers of α -amino acids which are joined to each other by:1 mkasked 3×
- Q11The half-life periods of decomposition of NH 3 for different initial pressures are given below: The order of the…1 mk
- Q12In the reaction of NaOBr with amide, the carbonyl carbon is lost as:1 mk
- Q121 mole of liquid A and 2 moles of liquid B make a solution having a total vapour pressure 40 torr. The vapour pressure…1 mk
- Q12Identify 'X' in the following reaction: 'X' is1 mk
- Q12Benzene diazonium chloride on reaction with phenol in weakly basic medium gives:1 mk
- Q12The deficiency of which of the following vitamins causes increased fragility of red blood cells and muscular weakness:1 mk
- Q12Which of the following reactions is not explained by the open chain structure of glucose?1 mkasked 3×
- Q12Benzene diazonium chloride on reaction with phenol in weakly basic medium gives1 mk
- Q12The polypeptide chain in a protein has amino acids linked with each other in a specific sequence. This specific…1 mkasked 3×
- Q12On hydrolysis, which of the following carbohydrates gives only glucose?1 mk
- Q12For the reaction 2A → 3B, the rate of reaction +(d[B])/(dt) is equal to:1 mk
- Q12Which of the following is a water-soluble vitamin?1 mk
- Q13Assertion: Alcohols act as Bronsted bases as well as Bronsted acids. Reason (R): Alcohols react as both nucleophiles…1 mk
- Q13Assertion: The presence of -OH group in phenols directs the incoming group to ortho and para positions. Reason (R): -OH…1 mk
- Q13Assertion: Separation of Zr and Hf is difficult. Reason (R): Zr and Hf have almost identical atomic and ionic radii due…1 mk
- Q13Assertion: Separation of Zr and Hf is difficult. Reason (R): Because Zr and Hf lie in the same group of the periodic…1 mk
- Q13Assertion: The presence of -OH group in phenols directs the incoming group at ortho- and para- positions. Reason (R):…1 mk
- Q13Assertion: D(+)- Glucose is dextrorotatory in nature. Reason (R): (+) represents dextrorotatory nature and D represents…1 mkasked 3×
- Q13Assertion: The molecularity of the given reaction is 2 2 HI → H 2+I 2 Reason (R): Two molecules of the reactants are…1 mkasked 3×
- Q13Assertion: It is not possible to separate the components of an azeotrope by fractional distillation. Reason (R):…1 mk
- Q13Assertion: Alcohols act as Bronsted bases as well as Bronsted acids. Reason (R): It is due to the presence of unshared…1 mk
- Q13Assertion:(CH 3) 3 C-O-CH 3 gives (CH 3) 3 C-I and CH 3 OH on reaction with HI. Reason (R): The reaction occurs by S N…1 mk
- Q13Assertion: Ethers have lower boiling points than the boiling points of alcohols. Reason (R): This is due to the…1 mk
- Q14Assertion: Actinoids show irregularities in their electronic configurations. Reason (R): Due to varying stabilities of…1 mk
- Q14Assertion: Zinc, cadmium and mercury are not considered as transition elements. Reason (R): These elements have…1 mkasked 3×
- Q14Assertion: Phenol is more acidic than 4-methylphenol. Reason (R): The presence of an electron releasing group in phenol…1 mk
- Q14Assertion: The presence of -OH group in phenols directs the incoming group to meta position in the ring. Reason (R):…1 mk
- Q14Assertion: Phenol is less acidic than 4-methylphenol. Reason (R): The presence of an electron releasing group in phenol…1 mk
- Q14Assertion: Diazonium salts of aromatic amines are more stable than those of aliphatic amines. Reason (R): Diazonium…1 mk
- Q14Assertion: Diazonium salts of aromatic amines are more stable than those of aliphatic amines. Reason (R): Diazonium…1 mk
- Q14Assertion: Highest oxidation state of Mn is +7 in first series of transition elements. Reason (R): Transition metals…1 mkasked 3×
- Q14Assertion: Diazonium salts of aromatic amines are less stable than those of aliphatic amines. Reason (R): Diazonium…1 mk
- Q14Assertion: Actinoids show irregularities in their electronic configurations. Reason (R): In actinoids 5f, 6d and 7s…1 mk
- Q15Assertion: p-nitrophenol is more acidic than phenol. Reason (R): Nitro group is an electron-withdrawing group, it…1 mkasked 3×
- Q15Assertion: Aromatic primary amines can easily be prepared by Gabriel phthalimide synthesis. Reason (R): Gabriel…1 mk
- Q15Assertion: Aromatic primary amines cannot be prepared by Gabriel phthalimide synthesis. Reason (R): Gabriel phthalimide…1 mk
- Q15Assertion: For complex reaction, order of reaction is given by the fast step. Reason (R): Order of reaction is…1 mk
- Q15Assertion: Components of azeotropes are easily separated by fractional distillation. Reason (R): Components of an…1 mk
- Q15Assertion: For complex reaction, order of reaction is given by the slowest step. Reason (R): Order of a reaction is an…1 mk
- Q15Assertion: For complex reaction, order of reaction is given by the slowest step. Reason (R): Order of reaction is not…1 mk
- Q15Assertion: Aromatic primary amines can be prepared by Gabriel Phthalimide synthesis. Reason (R): Aryl halides do not…1 mkasked 3×
- Q15Assertion: The pentaacetate of glucose does not react with H 2 N-OH. Reason (R): It indicates the absence of free -CHO…1 mk
- Q15Assertion: Monobromination of aniline can be conveniently done by protecting the amino group by acetylation. Reason…1 mk
- Q16Assertion: Glucose gets oxidized to six carbon gluconic acid on reaction with bromine water. Reason (R): The carbonyl…1 mkasked 3×
- Q16Assertion: The pentaacetate of glucose does not react with H 2 N-OH. Reason (R): It indicates the presence of free -…1 mk
- Q16Assertion: E Sc^3+ / Sc^2+^O has low value. Reason (R): Because of the stability of Sc^3+ ion which has a noble gas…1 mk
- Q16Assertion: It is not possible to separate the components of an azeotrope by fractional distillation. Reason (R):…1 mk
- Q16Assertion: Order of reaction is applicable to elementary as well as complex reactions. Reason ( R ): Order of a…1 mk
- Q16Assertion: The two strands of DNA are complementary to each other. Reason (R): The hydrogen bonds are formed between…1 mk
- Q16Assertion: E Mn^2+ / Mn^o value is highly negative. Reason (R): Because Mn^2+ is highly stable due to half-filled 3 d^5…1 mk
- Q16Assertion: All aliphatic aldehydes give a positive Fehling's test. Reason (R): Aliphatic aldehydes are reduced by…1 mkasked 3×
- Q16Assertion: Order of reaction is not applicable for elementary reaction but applicable for complex reaction. Reason (R):…1 mk
- Q17The concentration of the reactant is reduced from 0.6 mol L^-1 to 0.2 mol L^-1 in 5 minutes in a first order reaction.…2 mkasked 3×
- Q171.00 molal aqueous solution of trichloroacetic acid is heated to its boiling point. Boiling point of this solution was…2 mk
- Q17Reactions of which order will show the rate to be independent of the concentration of the reactant? Give one example of…2 mkasked 3×
- Q17For the compound having molecular formula C 4 H 9 Br, write: the isomer which is most reactive towards S N 1…2 mkasked 3×
- Q17What type of deviation is shown by a mixture of chloroform and acetone from Raoult's law? Give reason. What will happen…2 mk
- Q17What type of deviation from Raoult's law is shown by a mixture of phenol and aniline? Give reason. What will happen to…2 mk
- Q17Write IUPAC names of the following compounds: [Ag(NH 3) 2][Ag(CN) 2] [Co(en) 3] 2(SO 4) 32 mk
- Q17What type of deviation from Raoult's law is shown by mixture of ethanol and acetone? Give reason. What will happen to…2 mk
- Q18Name the cell used in hearing aids and watches. Define conductivity. Why is direct current (DC) not used for the…2 mk
- Q18Explain the following with the help of Henry's law: (i) Bends (ii) Anoxia OR How does sprinkling of salt help in…2 mkasked 3×
- Q18What is the effect of denaturation on the structure of proteins? What are the common types of secondary structures of…2 mk
- Q18For a reaction A+B → Products, the rate law is: Rate =k[ A][B]^3/2 Write the overall order of the reaction. Can this…2 mkasked 3×
- Q18Name any two materials other than hydrogen that can be used as fuel in fuel cells. Define molar conductivity.2 mk
- Q18Write the formulas for the following coordination compounds: Mercury(I) tetrathiocyanato-S-cobaltate(III) Dichloridobis…2 mk
- Q18Why are haloarenes less reactive towards nucleophilic substitution reaction? Give two reasons.2 mkasked 3×
- Q18Define activation energy. 1 + 1 Write the unit of rate constant for (i) zero order reaction, (ii) second order reaction.2 mk
- Q18Define Effective collision. 1 + 1 Write the unit of (i) second order reaction and (ii) zero order reaction2 mk
- Q18Name the cell which was used in the Apollo space programme for providing electrical power. Define limiting molar…2 mk
- Q18Define Collision frequency. 1 + 1 Write the units of (i) first order reaction and (ii) zero order reaction2 mk
- Q19Complete the following equation: How will you convert nitromethane to methyl isocyanide?2 mkasked 2×
- Q19Why second ionization enthalpies of chromium and copper are exceptionally higher than those of their neighbouring…2 mk
- Q19Complete the equation: How will you convert chlorobenzene to p-chloroaniline?2 mk
- Q19Why is third ionization enthalpy of manganese very high? 1 + 1 Why Zn, Cd and Hg are not regarded as transition…2 mk
- Q19Write IUPAC names of the following coordination compounds: (i) [Ag(NH 3) 2][Ag(CN) 2] (ii) K 3[Fe(C 2 O 4) 3] OR (i)…2 mkasked 3×
- Q19Write IUPAC names of the following compounds: [Cr(NH 3) 4(ONO) Cl] NO 3 Na[Ag(CN) 2]2 mk
- Q19First ionization enthalpy of Cr is lower than that of Zn. Why? 1 + 1 Mention any one property of the transition…2 mk
- Q19Explain why, on addition of 1 mol of KCl to 1 litre of water, the boiling point of water increases, while the addition…2 mkasked 3×
- Q19Name the sugar present in sugarcane. What are the hydrolysis products of this sugar? Is this sugar a reducing sugar?2 mk
- Q20Differentiate between the following: (i) Peptide linkage and Glycosidic linkage (ii) Essential amino acids and…2 mk
- Q20How do you explain the following? Presence of an aldehyde group in glucose Presence of a primary alcoholic group in…2 mk
- Q20Following reaction takes place in one step: 2 A+B → 2 C How will the rate of above reaction change if the volume of the…2 mkasked 3×
- Q20Write IUPAC names of the following compounds: (i) [PtCl 2(en) 2] SO 4 (ii) (NH 4) 2[CoF 4] OR Define the following…2 mkasked 3×
- Q20What are the products obtained on hydrolysis of sucrose? What are essential amino acids?2 mkasked 2×
- Q20Write the hydrolysis products of lactose. What are non-essential amino acids?2 mk
- Q20Differentiate between the following: (i) Fibrous protein and Globular protein (ii) Peptide linkage and Phosphodiester…2 mk
- Q20Define coordination number. 1+1 Indicate the type of isomerism exhibited by the following complex: [Co(en) 3] Cl 32 mkasked 2×
- Q20What are the hydrolysis products of the following? Lactose DNA containing Thymine2 mk
- Q20Define didendate ligand. Give an example. 1 + 1 Indicate the type of isomerism exhibited by the given complex: [Pt(NH…2 mk
- Q21Differentiate between the following: 2 × 1 (i) Acidic amino acids and basic amino acids (ii) Nucleotide and Nucleoside2 mk
- Q21Write any two fat soluble vitamins. How will you confirm the presence of five - OH groups in a glucose molecule, which…2 mk
- Q21Write the major product in the following reaction: What happens when 2-Bromobutane is made to react with alcoholic…2 mk
- Q21Draw the structures of major products in each of the following reactions:2 mk
- Q21Draw the structure of the given compound: 4-Bromo-3-methylpent-2-ene What happens when chloroethane is treated with…2 mkasked 2×
- Q21Name the disease caused by the deficiency of Vitamin A. How will you confirm the presence of carbonyl group as an…2 mk
- Q21Draw the structures of major products in each of the following reactions: 2 (CH 3) 3 CBr+KOH [ Heat ] Ethanol2 mk
- Q21How do you explain the following? Presence of a straight chain in glucose Presence of five - OH groups in glucose which…2 mk
- Q21How do you explain the following? Presence of a carbonyl group in glucose Presence of five - OH groups in glucose2 mk
- Q21Name two water-soluble vitamins. How will you prove the absence of free - CHO group in the cyclic structure of glucose…2 mk
- Q21Draw the structures of major product(s) in each of the following reactions: CH 3 CH=C(CH 3) 2+HBr →2 mk
- Q22A solution containing 8.0 g of a non-volatile solute in 100 g of diethyl ether boils at 36.86 °C whereas pure diethyl…3 mk
- Q2260 g of glucose is dissolved in 250 g of water. Calculate the freezing point of this solution. ( molar mass of glucose…3 mk
- Q22When 1.5 g of a non-volatile solute was dissolved in 90 g of benzene, the boiling point of benzene got raised from…3 mk
- Q22The half-life period of a radioactive element is 1.5 × 10^10 years. Calculate the time in which the activity of the…3 mkasked 3×
- Q22For the first order thermal decomposition reaction, following data was obtained: C 2 H 5 Cl( g) → C 2 H 4( g)+HCl( g)…3 mk
- Q22Give reasons for the following: Alkyl halides, though polar, yet their solubility in water is very low.…3 mk
- Q22Gives the structures of A, B and C in the following reactions:3 mk
- Q22Calculate emf of the following cell at 298 K: Al( s) Al^3+(aq)(0.1 M) Ni^2+(aq)(0.01 M) Ni( s) (Given: E Ni^2+ /…3 mk
- Q22Write the structures of A, B and C in the following reactions:3 mk
- Q22Calculate emf of the following cell at 298 K: Cr(s) Cr^3+(aq)(0.1 M) Fe^2+(aq)(0.01 M) Fe(s) (Given: E Cr^3+ /…3 mk
- Q22Calculate emf of the following cell at 298 K: Zn( s) Zn^2+(aq)(0.1 M) Ag^+(aq)(0.01 M) Ag( s) (Given: E Zn^2+ /…3 mk
- Q23How will you obtain the following from benzene diazonium chloride? Write chemical equations involved: 3 []3 mk
- Q23State Kohlrausch's law of independent migration of ions. With the help of a curve, explain why it is not easy to…3 mkasked 3×
- Q23Give the structures of A, B and C in the following reactions: CH 3-Cl KCN A LiAlH 4 B [Δ]CHCl 3+ alc. KOH C3 mk
- Q23How do you convert the following? Toluene to Benzaldehyde Benzoyl chloride to Acetophenone Bromobenzene to Benzoic acid…3 mk
- Q23Answer the following: (i) Why is the Equilibrium Constant (K c) related to E cell^° and not to E cell? (ii) Two metals…3 mkasked 3×
- Q23Define order of a reaction. The rate for the following reaction is given by: A+B → C Rate =k[A][B]^2 (i) How is the…3 mkasked 3×
- Q23What happens when: Propanenitrile is treated with phenyl magnesium bromide followed by hydrolysis? p-fluorotoluene is…3 mkasked 3×
- Q23Calculate emf of the following cell at 298 K: Sn Sn^2+(0.001 M) H^+(0.01 M) H 2( g)(1 bar ) Pt (s) Given: E^0 Sn^2+ /…3 mkasked 3×
- Q24The rate of the chemical reaction doubles when the temperature is raised from 298 K to 308 K. Calculate activation…3 mk
- Q24The rate of a particular reaction quadruples when the temperature increases from 293 K to 313 K. Calculate the energy…3 mk
- Q24Calculate the boiling point of a solution containing 0.61 g of benzoic acid (Molar mass =122 g mol^-1 ) in 5 g of CS 2…3 mkasked 3×
- Q24Answer the following questions: Why is direct current (DC) not used to measure the resistance of an ionic solution? Why…3 mkasked 3×
- Q24Complete and balance the following equations: 2+1 (i) 4 FeCr 2 O 4+8 Na 2 CO 3+7 O 2 → (ii) 5 Fe^2++MnO 4^-+8 H^+ →…3 mk
- Q24Complete and balance the following equations: (i) 2 KMnO 4 513 K (ii) Na 2 Cr 2 O 7+2 KCl → Why is it difficult to…3 mk
- Q24The rate of a particular reaction quadruples when the temperature increases from 300 K to 320 K. Calculate the energy…3 mk
- Q24An organic compound with molecular formula C 3 H 5 N on reaction with C 6 H 5 MgBr followed by hydrolysis, gives a…3 mkasked 3×
- Q24Complete and balance the following equations: (i) 2 Na 2 CrO 4+2 H^+ → (ii) 5 S^2-+2 MnO 4^-+16 H^+ → Why is chemistry…3 mk
- Q25[Co(NH 3) 6]^3+ is diamagnetic whereas [CoF 6]^3- is paramagnetic. Justify the statement. [Atomic number of Co=27 ]…3 mk
- Q25[Fe(H 2 O) 6]^2+ is paramagnetic whereas [Fe(CO) 5] is diamagnetic. Justify the statement. [Atomic number of Fe=26 ]…3 mk
- Q25When a coordination compound CoCl 3 · 6 NH 3 is mixed with excess of AgNO 3 solution, 3 moles of AgCl are precipitated…3 mkasked 3×
- Q25An antifreeze solution is prepared by dissolving 31 g of ethylene glycol (Molar mass =62 g mol^-1 ) in 600 g of water.…3 mkasked 3×
- Q25Write the IUPAC name of the given complex: [Co(NH 3) 4(H 2 O) Cl] Cl 2 Define polydentate ligand. Give an example.…3 mk
- Q25Write the IUPAC name of the given complex: K 2[Zn(OH) 4] Differentiate between a double salt and a complex. Mention the…3 mk
- Q25Define the following terms: Anomers Invert sugar Glycosidic linkage3 mk
- Q25How will you obtain the following from aniline? Write the chemical equations involved: Sulphanilic acid…3 mk
- Q25Answer the following questions about the complexes [NiCl 4]^2- and [Ni(CN) 4]^2- (i) Write the hybridization involved…3 mkasked 3×
- Q25Write the reactions of D-Glucose with the following: HI Br 2 water Conc. HNO 33 mk
- Q25Write the IUPAC name of the following complex: K 3[Cr(C 2 O 4) 3] Differentiate between homoleptic complex and…3 mk
- Q25Explain why [Fe(H 2 O) 6]^3+ is strongly paramagnetic whereas [Fe(CN) 6]^3- is weakly paramagnetic. [Atomic number of…3 mk
- Q26Write the major product in the following reactions: 1+1+1 Define Racemic mixture. p-dichlorobenzene has a higher…3 mk
- Q26Calculate the vapour pressure of a solution containing 61 g of benzoic acid (molar mass =122 g mol^-1 ) dissolved in…3 mkasked 3×
- Q26A coordination compound CrCl 3 · 6 H 2 O is mixed with excess of AgNO 3 solution, two moles of AgCl are precipitated…3 mk
- Q26Give reasons for the following: Although chlorine is an electron-withdrawing group, yet it is ortho-, para-directing in…3 mk
- Q26A coordination compound CrCl 3 · 6 H 2 O is mixed with excess of AgNO 3 solution, three moles of AgCl are precipitated…3 mk
- Q26Write the major product in the following reaction: 1+1+1 Define Chirality. Why racemisation occurs in S N 1 reaction?3 mk
- Q26A coordination compound CrCl 3 · 6 H 2 O is mixed with excess of AgNO 3 solution, one mole of AgCl is precipitated per…3 mk
- Q26Write the IUPAC name of the given compound: CH 3 CH(CH 3) CH(Br) CH 3 1+1+1 Define Racemisation. The boiling points of…3 mk
- Q26Give reasons for the following: Carboxylic acids have higher boiling point than alcohols of comparable molecular…3 mkasked 3×
- Q26How do you explain the presence of following in open structure of glucose? all the six carbon atoms are in a straight…3 mk
- Q27Consider the decomposition of hydrogen peroxide (H 2 O 2) as per the equation given below: 2 H 2 O 2 [ Alkaline medium…3 mkasked 3×
- Q27Write the reaction involved in the following: Reimer-Tiemann reaction Kolbe's reaction Friedal-Crafts acylation of…3 mkasked 3×
- Q27How will you obtain the following from benzenediazonium chloride? Give chemical equations involved: Chlorobenzene…3 mk
- Q27Write the reaction involved in 1+1+1 Rosenmund's reduction Cannizzaro's reaction Hell - Volhard - Zelinsky reaction3 mkasked 3×
- Q27How do you convert the following? Benzene to m-Nitroacetophenone Bromobenzene to 1-Phenylethanol But-3-en-2-one to…3 mk
- Q27How do you convert the following? Acetophenone to Benzoic acid Acetonitrile to Acetone Benzoic acid to Benzene3 mk
- Q28Define the following term: 2+1 Reducing sugar Differentiate between the following: (i) Fibrous proteins and globular…3 mk
- Q28Give reasons for the following: Haloalkanes react with KCN to form alkyl cyanides, while with AgCN, they form…3 mk
- Q28Define the following terms: 1+1+1 (i) Invert Sugar (ii) Polysaccharides On the basis of structure differentiate between…3 mk
- Q28Define the following terms: 2+1 (i) Denaturation as related to proteins (ii) Oligosaccharides On the basis of structure…3 mk
- Q28Compound 'X' with molecular formula C 4 H 9 Br reacts with aqueous KOH to give an alcohol. The rate of this reaction…3 mkasked 3×
- Q28Answer the following: Which isomer of C 4 H 9 Br is most reactive towards S N 1 reaction? Predict the alkene that would…3 mkasked 3×
- Q28(i) Arrange the following compounds in increasing order of their acidic strengths: (ii) Why is CH 3 CHO more reactive…3 mkasked 3×
- Q29Ethers are prepared by the dehydration of alcohols in presence of protic acids at 413 K. Symmetrical and unsymmetrical…4 mkasked 3×
- Q29The reaction of amines with mineral acids to form ammonium salts shows that these are basic in nature. Aliphatic amines…4 mkasked 3×
- Q29Alcohols and Phenols are acidic in nature. Electron withdrawing groups in phenol increase its acidic strength and…4 mkasked 3×
- Q29Living systems are made up of various complex biomolecules like carbohydrates, proteins, nucleic acids, lipids, etc.…4 mkasked 3×
- Q29Osmosis is a process by which the molecules of a solvent pass from a solution of low solute concentration to a solution…4 mkasked 3×
- Q30Carbohydrates are optically active polyhydroxy aldehydes or ketones or the compounds which produce such units on…4 mkasked 3×
- Q30Electrochemistry is the study of the relationship between chemical energy and electrical energy. Many spontaneously…4 mkasked 3×
- Q30Alcohols have higher boiling points than other compounds, namely hydrocarbons, ethers and haloalkanes of comparable…4 mkasked 3×
- Q30Like NH 3, nitrogen atom of amine is trivalent and carries an unshared pair of electrons. Nitrogen orbitals in amines…4 mkasked 3×
- Q30The Valence Bond Theory (VBT) explains the formation, magnetic behaviour and geometry of coordination compounds. The…4 mkasked 3×
- Q31(i) Describe giving reason which one of the following pairs has the property indicated: (I) Fe or Cu - higher melting…5 mkasked 3×
- Q31(i) Account for the following: (I) MnO is basic while Mn 2 O 7 is acidic. (II) Iron has higher enthalpy of atomization…5 mkasked 3×
- Q31(i) An organic compound (X) has the molecular formula C 5 H 10 O. Draw structures for (X) if it: 3 + 2 (I) does not…5 mkasked 3×
- Q31(i) Calculate the freezing point of a solution when 10 · 5 g of MgBr 2 was dissolved in 250 g of water, assuming MgBr 2…5 mkasked 3×
- Q31How will you convert the following: 3 + 2 (i) Propanone to Propene (ii) Benzoic acid to Benzaldehyde (iii) Benzene to…5 mkasked 3×
- Q32The conductivity of 0.1 mol L^-1 solution of NaC l is 1.06 × 10^-2 S cm^-1. Calculate its molar conductivity and degree…5 mkasked 3×
- Q32(i) (I) Why do transition metals show variable oxidation states? (II) Out of Mn^2+ and Ti^2+ which will be more…5 mkasked 3×
- Q32(i) From the given data of E^° values, answer the following questions: (I) Why E M^2+ / M^° show irregular trend in the…5 mkasked 3×
- Q32(i) How will you bring about the following conversions: (I) Bromobenzene to 1-phenylethanol (II) Benzene to…5 mkasked 3×
- Q33(i) Write the product(s) when: (I) One mol of ethanal is treated with 1 mol of CH 3 OH in the presence of dry HCl gas.…5 mkasked 3×
- Q33(i) (I) Which of the following is more reactive towards S N 1 reaction: 2-Bromo-2-methylbutane or 1-Bromopentane (II)…5 mkasked 3×
- Q33An organic compound 'A', with molecular formula C 2 H 6 O reacts with active metals such as sodium to give compound 'B'…5 mkasked 3×
- Q33(i) Calculate the electrode potential of a half-cell for zinc electrode dipping in 0.01 M ZnSO 4 solution at 25°C.…5 mkasked 3×
- Q33Calculate emf and Δ G for the following cell at 298 K: OR For the reaction: 2 AgCl( s)+H 2( g)(0.4 atm) → 2 Ag( s)+2…5 mkasked 3×
- Q33(i) Calculate E cell^0 for the following reaction which is at equilibrium: Cu(s)+2 Ag^+(aq) Cu^2+(aq)+2 Ag(s)…5 mkasked 3×
Other Chemistry years
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