List of top Chemistry Questions asked in CBSE CLASS XII

How will you confirm the presence of five –OH groups in a glucose molecule, which are attached to different carbon atoms?
For a reaction : \( N_2 + 3H_2 \rightarrow 2NH_3 \), the rate of reaction with respect to \( NH_3 \) is
Following reaction takes place in one step :
\( 2A + B \rightarrow 2C \)
How will the rate of above reaction change if the volume of the reaction vessel is decreased to one third of its original volume? Will there be any change in the order of reaction with the reduced volume?
Consider the following reaction and identify A and B: \[ CH_3Cl + NaI \xrightarrow{\text{dry acetone}} A + B \]
Write IUPAC names of the following coordination compounds:
(i) \( [Ag(NH_3)_2][Ag(CN)_2] \)
(ii) \( K_3[Fe(C_2O_4)_3] \)
Benzoic acid to Benzene
Name the cell which was used in the Apollo space programme for providing electrical power.
Assertion (A): Highest oxidation state of Mn is +7 in most of the transition elements.
Reason (R): Transition metals exhibit variable oxidation states.
Half-life (\( t_{1/2} \)) of a first order reaction is 1386 s. The value of rate constant is:
Assertion (A): D(+)-Glucose is dextrorotatory in nature.
Reason (R): (+) represents dextrorotatory nature and D represents its configuration.
Which of the following Grignard Reagent will be used to prepare cyclohexylmethanol when treated with methanal?
Which of the reactions is used in the conversion of a ketone into hydrocarbon?
What happens when acidic solution of potassium permanganate is allowed to stand for sometime ? Give the equation involved. What is this type of reaction called ?
Why Cr has higher melting point than Mn ?
Why transition metals act as good catalyst ?
Name a member of the lanthanoid series
(I) which exhibits +4 oxidation state
(II) which exhibits +2 oxidation state.
Write the ionic equations for the oxidising action of potassium permanganate for its reaction with \(I^-\) in both acidic and alkaline solutions.
From the given data of \(E^{\circ}\) values, answer the following questions :
(I) Why \(E^{\circ}_{M^{2+}/M}\) show irregular trend in the above values ?
(II) Why is \(E^{\circ}_{Cu^{2+}/Cu}\) value exceptionally positive ?
(III) Why \(E^{\circ}_{Mn^{2+}/Mn}\) value is highly negative ?
Draw the structure of 'X' in the following reaction:
Write the name of the reagent to convert Ethanenitrile to Ethanal.
Give a simple chemical test to distinguish between benzoic acid and ethyl benzoate.
Arrange the following in increasing order of their reactivity towards HCN:
Di-tert. butyl ketone, Acetaldehyde, Acetone
Draw structure of the 2, 4-dinitrophenyl hydrazone derivative of benzaldehyde.
Show how each of the following compounds can be converted to benzoic acid:
(I) Acetophenone
(II) Ethyl benzene
An organic compound (X) has the molecular formula \(C_5H_{10}O\). Draw structures for (X) if it:
(I) does not give Tollen's test but gives a positive iodoform test.
(II) does not give Tollen's test and iodoform test but undergoes Aldol condensation.
(III) undergoes Cannizzaro's reaction.