List of top Questions asked in CBSE CLASS XII

Which of the following material is not suitable for making agitators in washing machines?
What capacity of washing machine would be suitable to handle a large load of clothes for washing in one cycle in a big hotel?
Use of is important for designing tools, machines and workstations to reduce stress and health problems of the workers at the workplace.
Which of the following is a Food Supplementation Programme?
Who does the actual cleaning of guest rooms and bathrooms in a hotel?
Beti Bachao Beti Padhao Yojana was started by the Government of India with which of the following objectives?
The product (X) obtained in the following reaction is:
product (X) obtained
Phenol does not undergo nucleophilic substitution reaction easily due to:
Assertion (A): \( p \)-nitroaniline is a weaker base than \( p \)-toluidine.
Reason (R): The electron-donating \( -NO_2 \) group in \( p \)-nitroaniline makes it a weaker base.
Assertion (A): \( \Delta_{\text{mix}} H \) for an ideal solution is not equal to zero.
Reason (R): A–B interactions in an ideal solution are the same as between A–A and B–B interactions.
Write the chemical equations when:
(a) Ethanal is treated with 2,4-dinitrophenylhydrazine?
(b) Propanone is treated with Zn(Hg) and conc. HCl?
For a chemical reaction \( R \to P \), the variation in the concentration \([R]\) vs time \( t \) plot is given as:
variation in the concentration

(a) Predict the order of the reaction and write the unit of rate constant (\( k \)) for this order of reaction.
(b) What is the slope of the curve?
All proteins on hydrolysis give:
Assertion (A): Fluoroacetic acid is a stronger acid than chloroacetic acid. Reason (R): This is due to greater electron-withdrawing nature of \( F \) than \( Cl \).
The suitable Grignard reagent used for the synthesis of
Grignard reagent

with methanal is:
Which of the following has the highest boiling point?
In the Arrhenius equation, when \( \log k \) is plotted against \( 1/T \), a straight line is obtained whose:
Which of the following is most reactive towards nucleophilic substitution reaction?
A zero-order reaction is one whose rate is independent of:
The system that forms maximum boiling azeotrope is:
Which of the following is the strongest acid?
Maltose is made up of:
The equilibrium \( \text{Cr}_2\text{O}_7^{2-} \rightleftharpoons 2\text{CrO}_4^{2-} \):
The following initial rate data were obtained for the reaction: \[ 2\text{NO (g)} + \text{Br}_2 \text{(g)} \rightarrow 2 \text{NOBr (g)} \] initial rate data were obtained for the reaction
Write the chemical equation when:
(a) Butan-2-one is treated with Zn(Hg) and conc. HCl.
(b) Two molecules of benzaldehyde are treated with conc. NaOH.