CBSE Class 12 Chemistry 2024
309 questions · 550 marks · 308 with the board’s own marking-scheme answer, 1 with no official answer on the site.
Marks by chapter
Counted from the 309 questions listed below, as the 2024 papers print them. CBSE allocates marks per unit, not per chapter — this is what was observed, not an official CBSE weightage. Every year compared →
| Chapter | Marks | Share |
|---|---|---|
| Biomolecules36 questions | 68 | 12.4% |
| Chemical Kinetics38 questions | 60 | 10.9% |
| Electrochemistry30 questions | 60 | 10.9% |
| Amines38 questions | 57 | 10.4% |
| Coordination Compounds22 questions | 54 | 9.8% |
| Solutions30 questions | 53 | 9.6% |
| Alcohols, Phenols and Ethers40 questions | 52 | 9.5% |
| Haloalkanes and Haloarenes26 questions | 52 | 9.5% |
| Aldehydes, Ketones and Carboxylic Acids26 questions | 50 | 9.1% |
| The d-and f-Block Elements23 questions | 44 | 8.0% |
309 questions from 2024
- Q1The molar ionic conductivities of Ca^2+ and Cl^- are 119.0 and 76.3 S cm^2 mol^-1 respectively. The value of limiting…1 mk
- Q1The product of oxidation of SO_3^2- with MnO_4^- in acidic medium is:1 mk
- Q1The molar ionic conductivities of Al^3+ and SO_4^2- are 189 S cm^2 mol^-1 and 160 S cm^2 mol^-1 respectively. The value…1 mk
- Q1Van't Hoff factor for K_2 SO_4 solution, assuming complete ionization is1 mk
- Q1The specific sequence in which amino acids are arranged in a protein is called its1 mk
- Q1The most stable oxidation state of Iron is:1 mk
- Q1Which one of the following first row transition elements is expected to have the highest third ionization enthalpy?1 mk
- Q1Which of the following ligands is an ambidentate ligand?1 mk
- Q1The correct order for the increasing oxidizing power in 3d series of transition elements is:1 mk
- Q1Which of the following does not show variable oxidation states?1 mk
- Q1The equilibrium Cr_2 O_7^2- ⇌ 2 CrO_4^2-:1 mk
- Q1When MnO_2 is fused with KOH in air, it gives:1 mk
- Q1The molar ionic conductivities of Mg^2+ and SO_4^2- are 106.0 S cm^2 mol^-1 and 160.0 S cm^2 mol^-1 respectively. The…1 mk
- Q1Which of the following ligands can show linkage isomerism in a coordination compound?1 mk
- Q2Ligand EDTA ^4- is an example of a:1 mk
- Q2The coordination number of Co in [Co(en)_3]^3+ is:1 mk
- Q2Which of the following compounds will give a ketone on oxidation with chromic anhydride (CrO_3)?1 mk
- Q2Which of the following is the strongest acid?1 mk
- Q2Consider the following reaction: Identify A and B from the given options:1 mk
- Q2On adding AgNO_3 solution to 1 mole of complex NiCl_2 · 4 NH_3, two moles of AgCl are formed. The secondary valency of…1 mk
- Q2The product formed as a result of reaction of CH_3 MgBr and CO_2 followed by hydrolysis is:1 mk
- Q2The correct name of the given reaction is Ar-N_2^+ X^- →Cu CN / KCN Ar-CN+N_21 mk
- Q2On adding AgNO_3 solution to 1 mole of CoCl_3 · 4 NH_3, one mole of AgCl is precipitated. The secondary valency of Co…1 mk
- Q2The type of isomerism shown by the complex [CoCl_2(en)_2]^+ is:1 mk
- Q3Which one of the following hybrid states is associated with low spin complex?1 mk
- Q3Maltose is made up of:1 mk
- Q3Which of the following is diamagnetic in nature?1 mk
- Q3Two among the three components of DNA are β -D-2-deoxyribose and a heterocyclic base. The third component is:1 mk
- Q3Which of the following acids represents Vitamin C?1 mk
- Q3Which of the following elements of 3d series of transition elements has the lowest Δ_a H^0?1 mk
- Q3Transition elements form alloys easily because they have:1 mk
- Q3Which one of the following complexes is non-ionisable?1 mk
- Q3Out of the following alkenes, the one which will produce tertiary butyl alcohol on acid catalysed hydration is1 mk
- Q3Which of the following ligand forms chelate complex?1 mk
- Q3Nucleotides are composed of a:1 mk
- Q4Consider the following reaction: The major product of the reaction is:1 mk
- Q4Consider the following reaction: The major product obtained is:1 mk
- Q4Consider the following reaction: The major product obtained is:1 mk
- Q4The system that forms maximum boiling azeotrope is:1 mk
- Q4For an electrolyte undergoing association in a solvent, the van't Hoff factor:1 mk
- Q4Which of the following alkyl halides will undergo S_N 1 reaction most readily?1 mk
- Q4Auto-oxidation of chloroform in air and light produces a poisonous gas known as1 mk
- Q4Rosenmund reduction is used for the preparation of Aldehydes. The catalyst used in this reaction is1 mk
- Q4Butanenitrile may be prepared by heating:1 mk
- Q4Which of the following contains sp^2 hybridised carbon bonded to X?1 mk
- Q4Which of the following is a benzylic halide?1 mk
- Q5Phenol dimerises in benzene having van't Hoff factor 0 · 54. Its degree of association is:1 mk
- Q5Which of the following is most acidic?1 mk
- Q5Phenol is less acidic than:1 mk
- Q5Which alkyl halide from the given options will undergo S_N 1 reaction faster?1 mk
- Q5A zero-order reaction is one whose rate is independent of:1 mk
- Q5Which one of the following compounds has the highest pK_a value?1 mk
- Q5Transition metals are known to make interstitial compounds. Formation of interstitial compounds makes the transition…1 mk
- Q5For the reaction X+2 Y → P, the differential form equation of the rate law is:1 mk
- Q5Which one of the following compounds has the lowest pK_a value?1 mk
- Q5Which of the following Grignard reagent will be used with methanal to prepare1 mk
- Q6A reaction A_2+B_2 → 2 AB occurs by the following mechanism: A_2 → A+A (slow); A+B_2 → AB+B (fast); A+B → AB (fast) Its…1 mk
- Q6(CH_3)_3 C-O-CH_3 reacts with HI to give:1 mk
- Q6The compound which undergoes S_N 1 reaction most rapidly is:1 mk
- Q6Isotonic solutions have the same1 mk
- Q6From the elements of 3d series given below, which element shows the maximum number of oxidation states?1 mk
- Q6CH_3-O-CH_3 when treated with excess HI gives:1 mk
- Q6(CH_3)_2 CH-O-CH_3 when treated with HI gives:1 mk
- Q6(CH_3)_2 CH-O-CH_3 reacts with HI to give:1 mk
- Q6The correct name of the given reaction is Ar-N_2^+ X^- →[ Cu powder ]HBr Ar-Br+N_2.1 mk
- Q6Anisole reacts with HI to give:1 mk
- Q6C_6 H_5-O-CH_3 when treated with HI gives:1 mk
- Q7Which of the following cell was used in Apollo space programme?1 mk
- Q7Which of the following is most reactive towards nucleophilic substitution reaction?1 mk
- Q7Decarboxylation of sodium benzoate on heating with soda lime gives:1 mk
- Q7In effective collisions the colliding molecules must have:1 mk
- Q7Ethanol on heating with conc. H_2 SO_4 at 413 K gives:1 mk
- Q7Which of the following compounds on treatment with benzene sulphonyl choride forms product insoluble in alkali?1 mk
- Q7The fraction of molecules having energy equal to or greater than activation energy is:1 mk
- Q7The correct Mathematical expression of Arrhenius equation is1 mk
- Q7Aspirin is formed by the acetylation of:1 mk
- Q7Acetic acid reacts with PCl_5 to give:1 mk
- Q7A compound (X) with the molecular formula C_3 H_8 O can be oxidized by strong oxidizing agents to another compound (Y)…1 mk
- Q7Visha took 4 text-tubes namely A, B, C & D containing CH_3 CH=CH_2, CH_3 CH_2 CH=CH_2, CH_3 CH=CH-CH_3 and (CH_3)_2…1 mk
- Q7Which of the following compounds will not react with benzene sulphonyl chloride?1 mk
- Q7Which of the following compounds on treatment with benzene sulphonyl choride forms an alkali-soluble precipitate?1 mk
- Q8Identify the primary amine from the given options:1 mk
- Q8Identify the secondary amine from the given options:1 mk
- Q8Identify the tertiary amine from the following:1 mk
- Q8Van't Hoff factor for KCl solution assuming the complete dissociation is1 mk
- Q8Which of the following amines gives carbylamine reaction?1 mk
- Q8The product (X) obtained in the following reaction is:1 mk
- Q8An azeotropic solution of two liquids has boiling point higher than either of them when it:1 mk
- Q8The order of increasing basicities of CH_3 NH_2(I),(CH_3)_2 NH(II), (CH_3)_3 N (III) and C_6 H_5 NH_2 (IV) in aqueous…1 mk
- Q8The rate of a reaction increases sixteen times when the concentration of the reactant increases four times. The order…1 mk
- Q8An azeotropic solution of two liquids has boiling point lower than either of them when it:1 mk
- Q8The formation of cyanohydrin from an aldehyde is an example of:1 mk
- Q8'Scurvy' is caused by the deficiency of vitamin:1 mk
- Q8The IUPAC name of is:1 mk
- Q8On mixing 10 mL of acetone with 50 mL of chloroform, the total volume of the solution will be:1 mk
- Q9Dehydration of tertiary alcohols with Cu at 573 K gives:1 mk
- Q9The unit of cell constant is:1 mk
- Q9Which of the following has the highest boiling point?1 mk
- Q9The vitamin which plays an important role in coagulating blood is:1 mk
- Q9The relative lowering of vapour pressure of an aqueous solution containing non-volatile solute is 0.0225. The mole…1 mk
- Q9Nucleophilic addition of Grignard reagent to ketones followed by hydrolysis with dilute acids forms:1 mk
- Q9In the Arrhenius equation, when log k is plotted against 1/T, a straight line is obtained whose:1 mk
- Q9During electrolysis of aqueous CuCl_21 mk
- Q9'Night-Blindness' is caused by the deficiency of Vitamin:1 mk
- Q10In a given graph of zero order reaction, the slope and intercept are:1 mk
- Q10Which of the following species can act as the strongest base?1 mk
- Q10Which of the following cell is used in inverter?1 mk
- Q10During electrolysis of aqueous solution of NaCl:1 mk
- Q10The reaction of an alkyl halide with sodium alkoxide forming ether is known as:1 mk
- Q10For a certain reaction R → products, a plot of log [R] vs. time gives a straight line with a slope of -1 · 25 s^-1. The…1 mk
- Q10Half-life period of a first order reaction is 1386 seconds. The rate constant (k) of the reaction is:1 mk
- Q10When a catalyst increases the rate of a chemical reaction, then the rate constant (k):1 mk
- Q10The half life of a first order reaction with rate constant (k) of 3 min^-1 is:1 mk
- Q10Phenol does not undergo nucleophilic substitution reaction easily due to:1 mk
- Q11Which of the following cells is used in hearing aids?1 mk
- Q11Match the reagents required for the given reactions: I. Oxidation of primary alcohols to (p) NaBH_4 aldehydes II.…1 mk
- Q11For a zero order reaction A → products, t_1 / 2 is:1 mk
- Q11The suitable Grignard reagent used for the synthesis of CH_3-CH-CH_2-OH with methanal is:1 mk
- Q11The correct order of the ease of dehydration of the following alcohols by the action of conc. H_2 SO_4 is:1 mk
- Q11The addition of catalyst during a chemical reaction alters which of the following quantities of the reaction?1 mk
- Q11Phenol on reaction with aqueous bromine at room temperature gives:1 mk
- Q11A 1% solution of solute 'X' is isotonic with a 6% solution of sucrose (molar mass =342 g mol^-1 ). The molar mass of…1 mk
- Q11When the initial concentration of a reactant is doubled in the reaction, the half life period remains same. The order…1 mk
- Q11In which of the following molecules, C atom marked with asterisk is chiral?1 mk
- Q11Dilution affects both conductivity as well as molar conductivity. Effect of dilution on both is as follows:1 mk
- Q12During the electrolysis of aqueous NaCl, the cathodic reaction is:1 mk
- Q12The rate of the reaction 2 A+B_2 → 2 AB is given by Rate =k[A]^2[ B_2]. The value of rate constant (k) can be increased…1 mk
- Q12The general electronic configuration of d-block elements is:1 mk
- Q12Which functional groups of glucose interact to form cyclic hemiacetal leading to pyranose structure?1 mk
- Q12All proteins on hydrolysis give:1 mk
- Q12Aniline on reaction with Bromine water gives:1 mk
- Q12Van't Hoff factor for Na_2 SO_4 · 10 H_2 O solution, assuming complete ionization is1 mk
- Q12For the reaction A+2 B → C+D. The order of the reaction is1 mk
- Q12For the elementary reaction P → Q, the rate of disappearance of 'P' increases by a factor of 8 upon doubling the…1 mk
- Q12Which of the following is a secondary cell?1 mk
- Q13Assertion: Aliphatic primary amines can be prepared by Gabriel phthalimide synthesis. Reason (R): Alkyl halides undergo…1 mk
- Q13Assertion: p-nitrophenol is less acidic than phenol. Reason (R): Nitro group is electron withdrawing and helps in the…1 mk
- Q13Assertion: Zr and Hf are of almost similar atomic radii. Reason (R): This is due to Lanthanoid contraction.1 mk
- Q13Assertion: Fluoroacetic acid is stronger acid than chloroacetic acid. Reason (R): This is due to greater electron…1 mk
- Q13Assertion: Addition of ethylene glycol to water lowers its freezing point. Reason (R): Ethylene glycol is insoluble in…1 mk
- Q13Assertion: Aniline is a weaker base than cyclohexylamine ( -NH_2 ). Reason (R): Aniline is resonance stabilized.1 mk
- Q13Assertion: Phenols are stronger acids than alcohols. Reason (R): Alkoxide ion is more stable than phenoxide ion.1 mk
- Q13Assertion: Bromination of Phenol can be carried out even in the absence of Lewis acid. Reason (R): - OH group of Phenol…1 mk
- Q13Assertion: When NaCl is added to water a depression in freezing point is observed. Reason (R): NaCl undergoes…1 mk
- Q13Assertion (A): Δ_mix H and Δ_mix V are zero for an ideal solution. Reason (R): The solution which obeys Raoult's law…1 mk
- Q13Assertion: Aromatic primary amines can be prepared by Gabriel phthalimide synthesis. Reason (R): Alkyl halide undergoes…1 mk
- Q13Assertion (A): Δ_mix H and Δ_mix V are zero for non-ideal solutions. Reason (R): Solute-solvent interactions are not…1 mk
- Q14Assertion: Benzoic acid does not undergo Friedel - Crafts reaction. Reason (R): Carboxyl group is deactivating and the…1 mk
- Q14Assertion: Uracil base is present in DNA. Reason (R): DNA undergoes self-replication.1 mk
- Q14Assertion: Order of reaction and molecularity are always same for complex reactions. Reason (R): Order is determined…1 mk
- Q14Assertion: Rate of reaction increases with increase in temperature. Reason (R): Number of effective collisions increase…1 mk
- Q14Assertion: The pK_a of O_2 N-CH_2-COOH is lower than that of CH_3-COOH. Reason (R): -NO_2 group shows electron…1 mk
- Q14Assertion: Vitamin C cannot be stored in our body. Reason (R): Vitamin C is water soluble and readily excreted in urine.1 mkasked 2×
- Q14Assertion: Rate of reaction decreases with increase in temperature. Reason (R): Number of effective collisions…1 mk
- Q14Assertion: Separation of Zr and Hf is difficult. Reason (R): Zr and Hf have similar radii due to lanthanoid contraction.1 mk
- Q14Assertion: Uracil base is present in RNA. Reason (R): RNA undergoes self-replication.1 mk
- Q14Assertion: p -nitroaniline is a weaker base than p -toluidine. Reason(R): The electron donating -NO_2 group in p…1 mk
- Q15Assertion: Ammonolysis of alkyl halides involves reaction between alkyl halide and ethanolic solution of ammonia.…1 mk
- Q15Assertion (A): Δ_mix H for an ideal solution is not equal to zero. Reason (R): A - B interactions in an ideal solution…1 mk
- Q15Assertion: Phenol on reaction with aqueous NaOH gives sodium phenoxide. Reason (R): This reaction supports the acidic…1 mk
- Q15Assertion: Diazonium salts of aromatic amines are more stable than those of aliphatic amines. Reason (R): Diazonium…1 mk
- Q15Assertion: Inversion of configuration is observed in S_N 2 reaction. Reason (R): The reaction proceeds with the…1 mk
- Q15Assertion: The boiling point of ethanol is higher than that of dimethyl ether. Reason (R): Dimethyl ether molecules are…1 mk
- Q15Assertion: Transition metals have high enthalpy of atomization. Reason (R): This is because transition metals have low…1 mk
- Q15Assertion: Diazonium salts of aliphatic amines are more stable than those of aromatic amines. Reason (R): Diazonium…1 mk
- Q15Assertion: The pK_a of ethanoic acid is lower than that of Cl-CH_2-COOH. Reason (R): Chlorine shows electron…1 mk
- Q15Assertion: p-methoxyphenol is a stronger acid than m-methoxy phenol. Reason (R): Methoxy group exerts +R effect at both…1 mk
- Q15Assertion: Fructose is a reducing sugar. Reason (R): Fructose does not reduce Fehling solution and Tollen's reagent.1 mk
- Q15Assertion (A): The boiling point of ethanol is higher than that of dimethyl ether. Reason (R): Ethanol molecules are…1 mk
- Q16Assertion: Aniline is a stronger base than ammonia. Reason (R): The unshared electron pair on nitrogen atom in aniline…1 mk
- Q16Assertion: Aniline does not undergo Friedel-Crafts reaction. Reason (R): Friedel-Crafts reaction is a nucleophilic…1 mk
- Q16Assertion: Separation of Zr and Hf is difficult. Reason (R): Zr and Hf are radioactive.1 mk
- Q16Assertion: Aniline does not undergo Friedel-Crafts reaction. Reason (R): Friedel-Crafts reaction is an electrophilic…1 mk
- Q16Assertion: When NaCl is added in water, elevation in boiling point is observed. Reason (R): Elevation in boiling point…1 mk
- Q16Assertion: p-methoxyphenol is a stronger acid than p-nitrophenol. Reason (R): Methoxy group shows +I effect whereas…1 mk
- Q16Assertion: Aniline undergoes Friedel-Crafts reaction. Reason (R): Aniline forms salt with AlCl_3, the Lewis acid in…1 mk
- Q16Assertion: Boiling point of butan-1-ol is higher than that of butan-1-amine. Reason (R): Being more polar, butan-1-ol…1 mk
- Q16Assertion: Inversion of configuration is observed when 1-Bromobutane is hydrolysed. Reason (R): The reaction is S_N 2…1 mk
- Q16Assertion: For a Daniell cell, Zn / Zn^2+(1 M) ∥ Cu^2+(1 M) / Cu with E^° cell =1.1 V, if the external opposing…1 mk
- Q16Assertion: p -nitroaniline is a weaker base than p -toluidine. Reason (R): The electron withdrawing effect of -NO_2…1 mk
- Q16Assertion: Acetanilide ( -NHCOCH_3 ) is less basic than aniline. Reason (R): Acetylation of aniline results in decrease…1 mkasked 2×
- Q17Write the reactions of glucose with: H_2 N-OH Br_2 water2 mk
- Q17A 6% solution of glucose (molar mass=180 g mol^-1 ) is isotonic with 2.5% solution of an unknown organic substance.…2 mk
- Q17Define molal depression constant. How is it related to enthalpy of fusion? OR What type of deviation is shown by…2 mk
- Q17Define the following terms: Faraday's second law of electrolysis Corrosion2 mk
- Q17What happens when D-glucose is treated with the following reagents? H_2 N-OH (CH_3 CO)_2 O2 mk
- Q17Define the following terms: Order of a reaction Activation energy 1 × 22 mk
- Q17Calculate the potential of Iron electrode in which the concentration of Fe^2+ ion is 0.01 M. ( E^0 Fe^2+ / Fe=-0.45 V…2 mk
- Q17Write the reactions of glucose with: HI (CH_3 CO)_2 O2 mk
- Q17Define the following terms: Molecularity of reaction Complex reaction2 mk
- Q17Define the following terms: Half life period (t_1 / 2) Effective collisions2 mk
- Q17Define the following terms: Essential amino acids Nucleotide2 mk
- Q17Which one of the following pairs of substances undergoes S_N 1 reaction faster and why? CH_3-CH_2-CH_2-Cl OR…2 mk
- Q17State: Kohlrausch law of independent migration of ions. Faraday's first law of electrolysis.2 mk
- Q18In the following pair of compounds, which compound undergoes S_N 1 reaction faster and why? OR Write the major product…2 mk
- Q18In a reaction, if the concentration of reactant ' X ' is tripled, the rate of reaction becomes twenty-seven times. What…2 mk
- Q18A first order reaction has a rate constant 1.25 × 10^-3 s^-1. How long will 5 g of this reactant take to reduce to 2.5…2 mk
- Q1818 g of a non-volatile solute is dissolved in 200 g of H_2 O freezes at 272.07 K. Calculate the molecular mass of…2 mk
- Q18A solution containing 60 g of a non-volatile solute in 250 g of water freezes at 270.67 K. Calculate the molar mass of…2 mk
- Q18Complete and balance the following chemical equations: KMnO_4 → heat 2 MnO_4^-+5 C_2 O_4^2-+16 H^+ →2 mk
- Q18What happens when D-glucose is treated with the following reagents? Br_2 water HCN2 mk
- Q18Calculate the molar mass of a compound when 6.3 g of it is dissolved in 27 g of chloroform to form a solution that has…2 mk
- Q18Define molecularity of the reaction. State any one condition in which a bimolecular reaction may be kinetically of…2 mk
- Q18Resistance of a conductivity cell filled with 0.2 mol L^-1 KCl solution is 200 Ω. If the resistance of the same cell…2 mk
- Q18Define the following terms: 1 × 2 Limiting molar conductivity (Λ^° m) Fuel cell2 mk
- Q18Classify the following sugars into monosaccharides and disaccharides: Galactose, Glucose, Lactose and Maltose2 mk
- Q19Which compound in the given pair would undergo S_N 2 reaction at a faster rate and why? CH_3-CH_2-I and CH_3-CH_2-Br…2 mk
- Q19Carry out the following conversions: (i) Nitrobenzene to Aniline (ii) Aniline to Phenol OR (i) Write a chemical test to…2 mk
- Q19Complete the following ionic equations: 2 MnO_4^-+5 SO_3^2-+6 H^+ → Cr_2 O_7^2-+14 H^++6 Fe^2+ →2 mk
- Q19Which of the following compounds will react more rapidly by S_N 1 reaction and why? or CH_3 CH_2 Br Arrange the…2 mk
- Q19What is lanthanoid contraction? Actinoid contraction is greater from element to element than lanthanoid contraction.…2 mk
- Q19What happens when D-glucose is treated with the following reagents? HI Conc. HNO_32 mk
- Q19Define the following terms: Peptide linkage Essential amino acids2 mk
- Q19Which of the following compounds will react more rapidly by S_N 2 reaction \& why? or Arrange the following compounds…2 mk
- Q19Write the chemical equations when: Pentan-3-one is treated with H_2 N-NH_2 followed by heating with KOH in high boiling…2 mk
- Q19Classify the following sugars into monosaccharides and disaccharides: Sucrose, Lactose, Glucose, Fructose2 mk
- Q19For a chemical reaction R → P, the variation in the concentration [R] vs time t plot is given as: Predict the order of…2 mk
- Q20Which halogen compound in the following pair will react faster in S_N 1 reaction and why? or Why is the dipole moment…2 mk
- Q20Write the stepwise mechanism of nucleophilic addition reactions in the carbonyl compounds. OR How will you convert the…2 mk
- Q20Draw the structures of major monohalo products in each of the following reactions: OR Give reasons for the following:…2 mk
- Q20Which halogen compound in the following pair will react faster in S_N 2 reactions and why? CH_3-CH_2-I OR CH_3-CH_2-Br…2 mk
- Q20Write the chemical equations when: Ethanal is treated with 2,4-dinitrophenylhydrazine? Propanone is treated with Zn(Hg)…2 mk
- Q20In the following pair of compounds, which compound undergoes S_N 2 reaction faster and why? Write the major product in…2 mk
- Q20Show that in case of a first order reaction, the time taken for completion of 99% reaction is twice the time required…2 mk
- Q20Complete and balance the following chemical equations: 3 MnO_4^2-+4 H^+ → Cr_2 O_7^2-+14 H^++6 Fe^2+ →2 mk
- Q21A first order reaction takes 40 min for 75 % decomposition. Calculate rate constant. [Given: log 2=0.30, log 4=0.60 ]2 mk
- Q21Give reaction of glucose with the following: HCN Conc. HNO_32 mk
- Q21Which halogen compound in the following pair will react faster in S_N 2 reaction and why? OR Why does the presence of…2 mk
- Q21What happens when Glucose reacts with Nitric acid? Write chemical equation. Write one structural difference between DNA…2 mk
- Q21A 3%solution of glucose (molar mass =180 g mol^-1 ) is isotonic with 2.5% solution of an unknown organic substance.…2 mk
- Q21A 4% solution of urea (molar mass =60 g mol^-1 ) is isotonic with 5.2% solution of an unknown organic substance.…2 mk
- Q21Define the following terms: Denaturation of protein Invert sugar2 mk
- Q21What happens when glucose reacts with bromine water? Write chemical equation. Two bases are mentioned below, identify…2 mk
- Q21Classify the following sugars into monosaccharides and disaccharides: Fructose, Lactose, Glucose, Maltose2 mk
- Q21Write two differences between order of reaction and molecularity of reaction.2 mk
- Q21Write the chemical equation when: Butan-2-one is treated with Zn(Hg) and conc. HCl. Two molecules of benzaldehyde are…2 mk
- Q21What happens when Glucose reacts with HI? Write chemical equation. Which type of bond holds a DNA double helix…2 mk
- Q22Draw the geometrical isomers of the given complex: [Pt(en)_2 Cl_2]^2+ Write the electronic configuration for d^4 ion if…3 mk
- Q22A solution is prepared by dissolving 5 g of a non-volatile solute in 200 g of water. It has a vapour pressure of 31.84…3 mk
- Q22When a certain conductivity cell was filled with 0.05 M KCl solution, it has a resistance of 100 ohm at 25°C. When the…3 mk
- Q22Draw the geometrical isomers of the given complex: [Co(en)_2 Cl_2]^+ Write the electronic configuration of d^4 ion if…3 mk
- Q22Draw the geometrical isomers of the given complex: [Pt(NH_3)_2 Cl_2]^2+ Write the electronic configuration of d^5 ion…3 mk
- Q23The following initial rate data were obtained for the reaction: 2 NO( g)+Br_2( g) → 2 NOBr( g) What is the order with…3 mk
- Q23Calculate emf of the following cell at 25 °C: Sn / Sn^2+(0.001 M) ∥ H^+(0.01 M)|H_2( g)(1 bar)| Pt_(s) Given: E^°(Sn^2+…3 mk
- Q23Give the structure of the major product expected from the following reactions: 1 × 3 Reaction of Ethanal with…3 mk
- Q23The conductivity of 0 · 2 M solution of KCl is 2 · 48 × 10^-2 S cm^-1. Calculate its molar conductivity and degree of…3 mk
- Q23Calculate emf of the following cell: Zn(s)|Zn^2+(0 · 1 M)||Sn^2+(0 · 001 M)| Sn(s) Given: E_Zn^2+ / Zn^0=-0 · 76 V,…3 mk
- Q23Write the reaction involved in the following: Wolff-Kishner reduction Decarboxylation reaction Cannizzaro reaction3 mk
- Q24The vapour pressure of a solvent at 283 K is 100 mm Hg. Calculate the vapour pressure of a dilute solution containing 1…3 mk
- Q24Give the equations of reactions for the preparation of: (any three) Phenol from chlorobenzene Salicylaldehyde from…3 mk
- Q24Draw the structures of major product(s) in each of the following reactions: 1 × 33 mk
- Q24Write the IUPAC names of the following coordination compounds (any three): [Co(NH_3)_4 Cl(NO_2)] Cl [Ni(NH_3)_6] C l_2…3 mk
- Q24Write the formula for the following coordination compound: Potassium tetrahydroxidozincate (II) Arrange the following…3 mk
- Q24A first-order reaction is 25% complete in 40 minutes. Calculate the value of rate constant. In what time will the…3 mk
- Q25Give chemical tests to distinguish between the following pairs of compounds: (i) Phenol and Benzoic acid (ii) Propanal…3 mk
- Q25Calculate the emf of the following cell: 3 Ni(s)+2 Ag^+(0.01 M) → Ni^2+(0.1 M)+2 Ag(s) Given that E_cell^°=1.05 V, log…3 mk
- Q25Which of the following is an allylic halide? (i) CH_3-CH=CH-Br (ii) Out of chlorobenzene and…3 mk
- Q25Write the structures of A, B and C in the following reactions: CH_3-CH_2-Br →KCN A →[ Partial hydrolysis ]OH^- B…3 mk
- Q25Write IUPAC names of the following coordination compounds: (any three) K_3[Fe(CN)_6] [Pt(en)_2 Cl_2]^2+ [Co(NH_3)_4…3 mk
- Q25Give reasons for the following: Chlorine is ortho/para directing in electrophilic aromatic substitution reactions,…3 mk
- Q25What type of nucleophilic substitution (S_N 1. or.S_N 2) occurs in the hydrolysis of 2-Bromobutane to form…3 mk
- Q26Explain the following terms: Essential amino acids Peptide bond Denaturation 1 × 33 mk
- Q26Draw the structures of major product(s) in each of the following reactions: 1 × 33 mk
- Q26Write the equations of the reactions involved in the following: (i) Reimer-Tiemann reaction (ii) Kolbe's reaction Name…3 mk
- Q26Write the mechanism of the following reaction: CH_3 CH_2 OH →[443 K]H^+ CH_2=CH_2 Write the main product in each of the…3 mk
- Q26Define the following terms: Non essential amino acids. Monosaccharides Anomers 1 × 33 mk
- Q26Define the following terms: Glycosidic linkage Primary structure of protein Disaccharides 1 × 33 mk
- Q26Account for the following: 1 × 3 Haloalkanes react with AgCN to form isocyanide as main product. Allyl chloride shows…3 mk
- Q27Write the IUPAC name of the given compound: Why are haloalkanes more reactive towards nucleophilic substitution…3 mk
- Q27Give the structure of the major product expected from the following reactions: 1 × 3 Reaction of propanal with methyl…3 mk
- Q27Answer the following: (any three) What is peptide linkage? What type of bonds hold a DNA double helix together? Which…3 mk
- Q27Write the IUPAC name of the given compound: CH_2=CH-CH_2-CH_2-Cl Why is thionyl chloride preferred for preparing alkyl…3 mk
- Q27Write the IUPAC name of the given compound: The presence of -NO_2 group at ortho or para position increases the…3 mk
- Q27How will you bring about the following conversions? (any three) Benzoic acid to Benzaldehyde Ethanal to Propanone…3 mk
- Q27The rate constant of a reaction quadruples when the temperature changes from 300 K to 320 K. Calculate the activation…3 mk
- Q28Show that the time required for 99.9 % completion in a first order reaction is 10 times of half-life (t_1 / 2) of the…3 mk
- Q28Account for the following: 1 × 3 Haloalkanes react with NaCN to form both cyanides and isocyanides. Haloarenes do not…3 mk
- Q28Write chemical equations for the following reactions: (Do any three) Hydroboration - oxidation reaction Williamson…3 mk
- Q28A compound 'X' with molecular formula C_3 H_9 N reacts with C_6 H_5 SO_2 C l to give a solid, insoluble in alkali.…3 mk
- Q28The rate of a gaseous reaction triples when temperature is increased from 17^° C to 27^° C. Calculate the energy of…3 mk
- Q28The rate constant of a reaction quadruples when the temperature changes from 700 K to 720 K. Calculate the activation…3 mk
- Q28Give the structures of A, B and C in the following reactions: CH_3 CH_2 Cl →KCN A →LiAlH_4 B →[0^° C]HNO_2 C3 mk
- Q28Compound (C_6 H_12 O_2) on reduction with LiAlH_4 gives two compounds and. The compound on oxidation with PCC gives…3 mk
- Q29Batteries and fuel cells are very useful forms of galvanic cell. Any battery or cell that we use as a source of…4 mk
- Q29The nature of bonding, structure of the coordination compound can be explained to some extent by valence bond theory.…4 mk
- Q29The oxidation number of the central atom in a complex is defined as the charge it would carry if all the ligands are…4 mk
- Q29The oxidation number of the central atom in a complex is defined as the charge it would carry if all the ligands are…4 mk
- Q29Carbohydrates are essential for life in both plants and animals. Carbohydrates are used as storage molecules as starch…4 mk
- Q29The involvement of (n-1) d electrons in the behaviour of transition elements impart certain distinct characteristics to…4 mk
- Q30The Valence Bond Theory (VBT) explains the formation, magnetic behaviour and geometrical shapes of coordination…4 mk
- Q30In a galvanic cell, chemical energy of a redox reaction is converted into electrical energy, whereas in an electrolytic…4 mk
- Q30Certain organic compounds are required in small amounts in our diet but their deficiency causes specific disease. These…4 mk
- Q30Transition metals have incomplete d-subshell either in neutral atom or in their ions. The presence of partly filled…4 mk
- Q30Proteins are the most abundant biomolecules of the living system. Proteins are the polymers of about twenty different α…4 mk
- Q31(i) Calculate emf of the following cell at 25°C: Zn( s)|Zn^2+(0 · 001 M)||Cd^2+(0 · 1 M)| Cd( s) Given: E_Zn^2+ /…5 mk
- Q31An organic compound with the molecular formula C_9 H_10 O forms 2, 4-DNP derivative, reduces Fehling solution and…5 mk
- Q31Answer any five of the following: How is the crystal field splitting energy for octahedral complex (Δ_0) related to…5 mk
- Q31(i) At the same temperature, CO_2 gas is more soluble in water than O_2 gas. Which one of them will have higher value…5 mk
- Q31(i) Define reverse osmosis. (ii) Why are aquatic species more comfortable in cold water in comparison to warm water?…5 mk
- Q31Attempt any five of the following: Why Zinc is not regarded as a transition element? What is Lanthanoid contraction?…5 mk
- Q31Attempt any five of the following: 1 × 5 Ce(III) is easily oxidised to Ce(IV). Comment. E^°(Mn^2+ / Mn) is -1.18 V. Why…5 mk
- Q32(i) Write the major product(s) in the following reactions: (2) (3) (ii) Give simple chemical tests to distinguish…5 mk
- Q32Answer any five questions of the following: N,N-diethyl-benzenesulphonamide is insoluble in alkali. Give reason.…5 mk
- Q32(i) Account for the following: (1) Oxidation of aldehydes is easier as compared to ketones. (2) The alpha ( α )…5 mk
- Q32(i) Ishan's automobile radiator is filled with 1.0 kg of water. How many grams of ethylene glycol (Molar mass =62 g…5 mk
- Q33(i) Account for the following: (1) The melting and boiling points of Zn, Cd and Hg are low. (2) Of the d^4 species,…5 mk
- Q33Attempt any five of the following: Write the IUPAC name of the complex: [Co(H_2 O)(CN)(en)_2]^2+ Why is geometrical…5 mk
- Q33An amide 'A' with molecular formula C_7 H_7 ON undergoes Hoffmann Bromamide degradation reaction to give amine 'B'. B'…5 mk
- Q33(i) The resistance of 0.05 M CH_3 COOH solution is found to be 100 ohm. If the cell constant is 0.0354 cm^-1, calculate…5 mk
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