1
COMEDK 2025 Afternoon Shift
MCQ (Single Correct Answer)
+1
-0

Which is the correct order of increasing number of unpaired electrons in the following ions?

$$\mathrm{A}=\mathrm{Cr}^{2+}(\mathrm{Z}=24) \mathrm{B}=\mathrm{Cu}^{2+}(\mathrm{Z}=29) \quad \mathrm{C}=\mathrm{Ni}^{2+}(\mathrm{Z}=28) \mathrm{D}=\mathrm{Fe}^{3+}(\mathrm{Z}=26)$$

A
$\mathrm{B}<\mathrm{C}<\mathrm{A}<\mathrm{D}$
B
$\mathrm{D}<\mathrm{C}<\mathrm{A}<\mathrm{B}$
C
$\mathrm{B}<\mathrm{C}<\mathrm{D}<\mathrm{A}$
D
$\mathrm{C}<\mathrm{B}<\mathrm{D}<\mathrm{A}$
2
COMEDK 2025 Afternoon Shift
MCQ (Single Correct Answer)
+1
-0
Which one of the following is incorrect?
A
Rate constant equals the rate of reaction when concentration of reactants equals unity.
B
Larger the value of rate constant $(\mathrm{k})$ value faster is the chemical reaction.
C
The unit for rate constant for $n^{\text {th }}$ order reaction is $\left(\mathrm{mol} \mathrm{L}^{-1}\right)^{n-1} \mathrm{~s}^{-1}$
D
The value of rate constant $(\mathrm{k})$ is independent of concentration of reactants.
3
COMEDK 2025 Afternoon Shift
MCQ (Single Correct Answer)
+1
-0
A dilute solution of $\mathrm{K}_2 \mathrm{HgI}_4$ reagent is $95 \%$ ionised. What would be the approximate value of its van't Hoff factor?
A
1.85
B
1.50
C
2.05
D
2.90
4
COMEDK 2025 Afternoon Shift
MCQ (Single Correct Answer)
+1
-0
For a hypothetical chemical reaction $\mathrm{A}_2+3 \mathrm{~B}_2+$ Heat $\cdots\rightarrow 2 \mathrm{AB}_3$, which one of the following combinations of state variables would support the spontaneity of the reaction at a particular temperature?
A
$\Delta \mathrm{H}<0, \Delta \mathrm{~S}>0, \Delta \mathrm{G}>0$
B
$\Delta \mathrm{H}>0, \Delta \mathrm{~S}>0, \Delta \mathrm{G}<0$
C
$\Delta \mathrm{H}>0, \Delta \mathrm{~S}<0, \Delta \mathrm{G}<0$
D
$\Delta \mathrm{H}>0, \Delta \mathrm{~S}<0, \Delta \mathrm{G}>0$
EXAM MAP
Medical
NEETAIIMS
Graduate Aptitude Test in Engineering
GATE CSEGATE ECEGATE EEGATE MEGATE CEGATE PIGATE IN
Civil Services
UPSC Civil Service
Defence
NDA
Staff Selection Commission
SSC CGL Tier I
CBSE
Class 12