List of top Questions asked in UP Board XII

Unit of rate constant of a first order reaction is —
\( CH_3-CH_2-CH=CH_2 + HBr \xrightarrow{Peroxide} \) product. In this reaction, the main product is —
The unit of rate constant of a zero order reaction is —
Explain first order reaction with example.
Differentiate between order and molecularity of a reaction.
Lanthanide contraction is observed in —
IUPAC name of \( CH_3-CH_2-CH(OH)-CH_3 \) is —
i) Define standard electrode potential. (1)
ii) Define bidentate ligand. (1)
iii) Complete the following reactions (1+1+1):
a) RX + NaOR' → ?
b) C6H5COCH3 (acetophenone) + H2/Pd-BaSO4 → ?
c) C6H6 (benzene) + CO + HCl → (AlCl3/Cu2Cl2) ?
OR
i) Explain standard hydrogen electrode potential with diagram. (1)
ii) Give an example of optical isomerism. (1)
iii) Complete the following reactions (1+1+1):
a) CH3CH2OH → (H2SO4, 413 K) ?
b) RCN + SnCl2 + HCl → ?
c) C6H5CH3 (toluene) + CrO2Cl2 + CS2 → ?
Discuss the structure of glucose in detail. (5)
OR
i) What do you understand by mono, di and polysaccharides? Explain with examples. (3)
ii) What are peptide bonds and glycosidic bonds? (2)
What happens when (give only the chemical equations):
(i) Methyl phenyl ketone is treated with iodine in the presence of NaOH?
(ii) Ethyl bromide is heated with aqueous KOH?
(iii) Phenol reacts with chloroform in the presence of aqueous NaOH?
(iv) Acetaldehyde is treated with Tollen's reagent?
(v) Benzoic acid is heated with ammonia? (1+1+1+1+1)
OR
How would you obtain (write chemical equations only):
(i) Formic acid from formaldehyde?
(ii) Propane-2-ol from propene?
(iii) Benzene from phenol?
(iv) m-bromobenzoic acid from benzoic acid?
(v) Ethyl acetate from acetic acid? (1+1+1+1+1)

(i) Explain the mechanism of the Bimolecular Nucleophilic Substitution reaction (SN2) in a haloalkane and give the order of reactivity of the alkyl halides based on SN2. (3)
(ii) Name the reagent used in the following reactions: (x) Oxidation of a primary alcohol to an aldehyde. (y) Oxidation of a primary alcohol to a carboxylic acid. (2)
OR
Write the IUPAC names of the following compounds (1+1+1+1+1):
(i) (CH3)3C–Cl
(ii) CH3–CH2–CH(Br)–CH3
(iii) 4-F–C6H4–COCH3
(iv) a benzene ring bearing two CH3 groups and one OH group
(v) CH3–CH(CH3)–CH(CH3)–CH(OH)–C(CH3)3
(i) Explain reduction of nitriles, with chemical reaction.
(ii) Write only the chemical equation for the reaction that occurs when aniline is heated with chloroform in the presence of alcoholic KOH.
State Henry's law and its important applications.
(i) Write the electronic configuration of the following ions: (a) Cr3+ (b) Cu2+.
(ii) Write the formula of chromate and dichromate ions.
(i) How would you obtain chlorobenzene from diazonium salt and aniline from chlorobenzene? (Write only chemical equation.) (2)
(ii) Write the increasing order of basicity of the following compounds: NH3, (CH3)3N, CH3NH2, (CH3)2NH. (1)
(iii) What are the main sources of protein? (1)
What is Kohlrausch's law? If \( \lambda^{\circ}_m \) for NaCl, HCl and NaAc are 126.4, 425.9 and 91.0 S cm2 mol-1 respectively, find the value of \( \lambda^{\circ}_m \) for HAc. (2+2)
Write the uses of freon. What is its impact on the environment?
(i) What is meant by ambidentate ligand? Give examples also. (2)
(ii) Write the IUPAC names of following compounds:
a) [Co(Br)2(en)2]+
b) K3[Fe(C2O4)3] (1+1)
The rate constants of a certain reaction at 500 K and 700 K are 0.02 sec-1 and 0.07 sec-1 respectively. Calculate \( E_a \) and \( A \). (2+2)
What is an isotonic solution? Explain with an example.
Explain Aldol condensation with a chemical reaction.
The resistance of a conductivity cell filled with 0.1 mol L\(^{-1}\) KCl solution is 100 \( \Omega \). If the resistance of the same cell when filled with 0.02 mol L\(^{-1}\) KCl solution is 520 \( \Omega \), find the conductivity and molar conductivity of the 0.02 mol L\(^{-1}\) KCl solution. The conductivity of a 0.1 mol L\(^{-1}\) KCl solution is 1.29 S/m.
The freezing point decreases by 0.40 K, when 1.00 g non-electrolyte is dissolved in 50 g benzene. The value of \( K_f \) for benzene is 5.12 K kg mol\(^{-1}\). Calculate the molar mass of the solute.
What are the characteristics of transition metals? Why are they called transition metals?
What is meant by the chelate effect? Give example also.