List of top Chemistry Questions asked in CBSE CLASS XII

A zero-order reaction is one whose rate is independent of:
Which of the following is most reactive towards nucleophilic substitution reaction?
In the Arrhenius equation, when \( \log k \) is plotted against \( 1/T \), a straight line is obtained whose:
Maltose is made up of:
Which of the following is the strongest acid?
The system that forms maximum boiling azeotrope is:
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.
Define colligative property. Which colligative property is preferred for the molar mass determination of macromolecules?
What happens when D-glucose is treated with the following reagents?
1 molal aqueous solution of an electrolyte \( A_2B_3 \) is 60% ionized. Calculate the boiling point of the solution.
How does the size of blood cells change when placed in an aqueous solution containing more than 0.9% (mass/volume) sodium chloride?
What is peptide linkage?
Complete and balance the following chemical equations: 
Thermal decomposition of Potassium Permanganate
Consider the following reaction:
Identify A and B
Identify A and B from the given options:
Identify the tertiary amine from the following:
In a given graph of zero order reaction, the slope and intercept are:

zero order reaction
Write the chemical equations when: Two molecules of (CH3)3C–CHO are treated with conc. NaOH.
Alkyl halides give alcohol with aqueous KOH whereas in the presence of alcoholic KOH, alkenes are formed. Give reasons.
Grignard reagent should be prepared under anhydrous conditions. Give reasons.
A reaction A$_2$ + B$_2$ → 2AB occurs by the following mechanism:
A$_2$ → A + A (slow)
A + B$_2$ → AB + B (fast)
A + B → AB (fast)
Its order would be:
What happens when D-glucose is treated with the following reagents? 
(a) Br$_2$ water 
(b) HCN
Write the chemical equations when: Pentan-3-one is treated with H$_2$N–NH$_2$ followed by heating with KOH in high boiling solvent such as ethylene glycol.
Write two differences between order of reaction and molecularity of reaction.