1
COMEDK 2025 Afternoon Shift
MCQ (Single Correct Answer)
+1
-0
The rate constant for a zero order reaction $\mathrm{A} \rightarrow \mathrm{B}+\mathrm{C}$ is $6.0 \times 10^{-3} \mathrm{molL}^{-1} \mathrm{~s}^{-1}$. What would be the time taken for the initial concentration of A to decrease from 0.2 M to 0.024 M ?
A
15.83 s
B
37.34 s
C
31.90 s
D
29.33 s
2
COMEDK 2025 Afternoon Shift
MCQ (Single Correct Answer)
+1
-0
When one mole of a hydrocarbon $\mathbf{C}_{\mathbf{a}} \mathbf{H}_{\mathbf{b}}$ undergoes complete combustion, it requires 7.5 moles of $\mathrm{O}_2$ and results in the production of 6 moles of $\mathrm{CO}_2$. Calculate the values of $\mathbf{a}$ and $\mathbf{b}$.
A
$a=4$ and $b=10$
B
$a=6$ and $b=6$
C
$a=6$ and $b=12$
D
$a=4$ and $b=8$
3
COMEDK 2025 Afternoon Shift
MCQ (Single Correct Answer)
+1
-0
For the reaction $\mathrm{P}+\mathrm{Q} \leq \mathrm{R}+\mathrm{S}$, carried out at 298 K , the equilibrium constant was found to be 169 and the initial concentrations of all reactants and products was 1.0 M . What is the equilibrium concentration of the reactants?
A
0.143 M
B
0.462 M
C
0.857 M
D
0.698 M
4
COMEDK 2025 Afternoon Shift
MCQ (Single Correct Answer)
+1
-0

Two statements, one Assertion and the other Reason are given. Choose the correct option.

Assertion: Heterocyclic compounds like Pyridine and Thiophene are non-aromatic compounds.

Reason: According to Huckel rule for a given compound to exhibit aromaticity, the molecule must be planar, cyclic system having delocalised $(4 n+2) \pi$ electrons.

A
Assertion is correct but Reason is incorrect.
B
Both Assertion and Reason are incorrect.
C
Reason is correct but Assertion is incorrect.
D
Both Assertion and Reason are correct.
EXAM MAP