List of top Questions asked in KBPE

Complete the following:

1. Reactant: RCOCl
Reagent: H2 / Pd-BaSO4
Major Product: RCHO
Name of Reaction: Rosenmund Reduction

2. Reactant: CH3COOH
Reagent: Cl2 / Red P
Major Product: Cl-CH2COOH
Name of Reaction: HVZ Reaction

3. Reactant: CH3CHO
Reagent: Zn-Hg / conc. HCl
Major Product: CH3CH3
Name of Reaction: Clemmensen Reduction

(i)[Ni(CN)₄]²⁻ and [Ni(CO)(_4)] have different structures, but do not differ in their magnetic behaviour. Explain. 
(ii) Write the formula of Tetraamineaquachloridocobalt(III)chloride.

How do you prepare K₂Cr₂O₇ from chromite ore?

Give reasons for the following: 
(i) Zn, Cd and Hg are not considered transition elements. 
(ii) Transition metals form complex compounds. 
(iii) Sc(3+) is colourless, but Ti(3+) is coloured.

Briefly explain the electrochemical processes involved in the rusting of iron.
How will you convert nitrobenzene to 2, 4, 6-Tribromo aniline?
Give one chemical test to distinguish between formaldehyde and acetaldehyde.
How methanol is prepared industrially? Write the chemical equation.
In the electrolysis of molten NaCl, the substance liberated at the cathode is:
Which of the following is least reactive towards nucleophilic substitution (\( S_N1 \))?

(i) Explain Aldol condensation with example.
(ii) How are the following conversions achieved: 
(a) Benzene  Benzaldehyde, (b) Ethanoic acid  ethanol.

Why saline water is mixed with medicine before injected into the blood of a patient?
Which of the following is a polysaccharide?
Which of the following is a chelating ligand?
The half-life of a first-order reaction depends on:
The initial concentration of the first order reaction:

N2O5 (g) → 2NO2 (g) + 1/2 O2 (g)

was 1.24 × 10⁻² mol L⁻¹ at 300 K. The concentration of N2O5 after 60 minutes was 0.20 × 10⁻² mol L⁻¹.

Calculate the rate constant of the reaction at 300 K.
The standard electrode potential for Daniell cell is 1.1 V. Calculate the standard Gibbs energy change for the reaction:

Zn(s) + Cu2+(aq) → Zn2+(aq) + Cu(s)
Identify the products X and Y formed in the following reactions:

(i) CH3CH2OH + PCl5 → X + POCl3 + HCl

(ii) CH3Br + AgF → Y + AgBr

Give two differences between N1 and N2 reactions.

200 cm3 of an aqueous solution of a protein contains 1.26 g of the protein. The osmotic pressure of this solution at 300 K is found to be 2.57 × 10^-3 bar. Calculate the molar mass of the protein.

Given: R = 0.083 L bar mol^-1 K^-1

(i) Write any two differences between order and molecularity. 
(ii) What do you mean by pseudo order reaction?

(i) Draw the diagram which indicates the splitting of d-orbitals in tetrahedral field. 
(ii) Write any one limitation of valence bond theory.

Name the products formed when phenol is treated with the following reagents: 
(i) Bromine water 
(ii) Zinc dust 
(iii) Conc. HNO_3 

(i) The reaction in which an amide is converted into a primary amine by the action of Br2 and alcoholic NaOH is known as ________.

(ii) How is a primary amine distinguished from a secondary amine using the Hinsberg test?

(i) Differentiate between globular and fibrous proteins. 
(ii) What is meant by denaturation of protein?