1
COMEDK 2026 Morning Shift
MCQ (Single Correct Answer)
+1
-0

Identify the correct values to be plotted in the graph, the slope of which can be used to determine the activation energy of a reaction.

A

$\ln k $ vs $\frac{1}{T}$

B

$\ln k $ vs $T$

C

$\frac{\ln k}{T} $ vs $T$

D

$\frac{T}{\ln k}$ vs $\frac{1}{T}$

2
COMEDK 2026 Morning Shift
MCQ (Single Correct Answer)
+1
-0

The ion that has a spin only magnetic moment of 5.9 BM is:

A

$\mathrm{Fe}^{3+}$

B

$\mathrm{Mn}^{3+}$

C

$\mathrm{Ni}^{2+}$

D

$\mathrm{Co}^{3+}$

3
COMEDK 2026 Morning Shift
MCQ (Single Correct Answer)
+1
-0

In the reaction,

$$ \mathrm{Cr}_2 \mathrm{O}_7^{2-}+4 \mathrm{H}_2 \mathrm{O}_2+2 \mathrm{H}^{+} \rightarrow 2 \mathrm{CrO}_5+\mathrm{H}_2 \mathrm{O} $$

The change in oxidation state of Cr is:

A

+6 to +3

B

+6 to +10

C

No change in oxidation state

D

+3 to +6

4
COMEDK 2026 Morning Shift
MCQ (Single Correct Answer)
+1
-0

$$ \text { Match the Coordination compounds in Column I with the type of stereoisomerism given in Column II exhibited by them. } $$

$$
\text { Column I }
$$
$$
\text { Column I }
$$
A $$
\left[\mathrm{Pt}\left(\mathrm{NH}_3\right)_2 \mathrm{Cl}_2\right]
$$
P fac-mer
B $$
\mathrm{Ni}\left[\left(\mathrm{NH}_3\right)_2 \mathrm{Cl}_2\right]
$$
Q cis -trans
C $$
\left[\mathrm{Co}\left(\mathrm{NH}_3\right)_3\left(\mathrm{NO}_2\right)_3\right]
$$
R only cis isomer shows optical isomerism
D $$
\left[\mathrm{Pt} \mathrm{Cl}_2(\mathrm{en})_2\right]^{2+}
$$
S does not exhibit isomerism.
A

$$ A-S \quad B-R \quad C-Q \quad D-P $$

B

$$ A-S \quad B-P \quad C-Q \quad D-R $$

C

$$ A-Q \quad B-S \quad C-O \quad D-R $$

D

$$ A-R \quad B-P \quad C-S \quad D-Q $$