List of top Chemistry Questions asked in CBSE CLASS XII

Why is \([Ni(H_2O)_6]^{2+}\) coloured? (Atomic number of Ni = 28)
Write the oxidation state and hybridisation of the central metal in the following complex: \[ [Fe(H_2O)_6]^{3+} \quad (\text{Atomic number of Fe = 26}) \]
A coordination compound CrCl\(_3 \cdot 6H_2O\) is mixed with excess AgNO\(_3\) solution, two moles of AgCl are precipitated per mole of the compound. Write the structural formula of the coordination compound.
Which type of isomerism is exhibited by the following complex? \[ [Pt(NH_3)_2Cl_2] \]
Differentiate between homoleptic complex and heteroleptic complex.
Write the IUPAC name of the following complex: \[ K_3[Cr(C_2O_4)_3] \]
The rate of a chemical reaction doubles when the temperature is raised from 298 K to 308 K. Calculate the activation energy (\(E_a\)) for this reaction assuming it does not change with temperature. (Given: \( R = 8.314 \, \text{J mol}^{-1}\text{K}^{-1} \), \( \log 2 = 0.30 \))
Write the overall order of a reaction if A is present in large excess.
Define order of a reaction.
Write any two fat soluble vitamins.
What are essential amino acids?
What are the products obtained on hydrolysis of sucrose?
How will you convert nitromethane to methyl isocyanide?
Complete the following equation:
Define limiting molar conductivity.
State Henry’s law. Calculate the mole fraction of CO\(_2\) in water at 298 K under 700 mm Hg pressure. (Given: Henry’s constant for CO\(_2\) in water at 298 K = \( 1.25 \times 10^6 \) mm Hg)
1.00 molal aqueous solution of trichloroacetic acid is heated to its boiling point. The boiling point of this solution was found to be 100.18\(^\circ\)C. Calculate the Van’t Hoff factor for trichloroacetic acid. (Given: \( K_b \) for water = 0.512 K kg mol\(^{-1}\))
Assertion (A): All aliphatic aldehydes give a positive Fehling's test.
Reason (R): Aliphatic aldehydes are reduced by Fehling's reagent.
Assertion (A): p-nitrophenol is more acidic than phenol.
Reason (R): Nitro group is an electron-withdrawing group; it stabilizes phenoxide ion by dispersal of negative charge.
The polypeptide chain in a protein has amino acids linked with each other in a specific sequence. This specific sequence of amino acids is called:
Identify the polysaccharide among the following:
Consider the following compounds: \[ (C_2H_5)_2NH,\quad C_6H_5NH_2,\quad C_6H_5CH_2NH_2,\quad NH_3,\quad (C_2H_5)_3N \] The correct increasing order of the above bases on the basis of their basic strength is:
Primary, secondary and tertiary alcohols can be distinguished by:
Which of the following ligands forms a chelate complex?
The correct formula of Hinsberg's reagent is: