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

What is the standard electrode potential at 298 K for the reaction: $\mathrm{Cu}^{2+}+1 \mathrm{e}-\rightarrow \mathrm{Cu}^{+1}$ ?

Given: $\mathrm{E}_0 \mathrm{Cu}^{+1} / \mathrm{Cu}=0.5 \mathrm{~V} \quad \& \quad \mathrm{E}_0 \mathrm{Cu}^{+2} / \mathrm{Cu}=0.335 \mathrm{~V}$

A
0.34V
B
0.17V
C
0.492V
D
0.410V
2
COMEDK 2025 Afternoon Shift
MCQ (Single Correct Answer)
+1
-0

The Standard Reduction potential at $25^{\circ} \mathrm{C}$ for $\left(\mathrm{MnO}_4\right)^{-1} / \mathrm{H}^{+}$is +1.49 V . The $\mathrm{E}^0$ values for four Metal ions :

(a). $\mathrm{Co}^{3+} / \mathrm{Co}^{2+}$

(b). $\mathrm{Cr}^{3+} / \mathrm{Cr}$

(c). $\mathrm{Au}^{3+} / \mathrm{Au}$ and

(d). $\mathrm{Ag}^{+} / \mathrm{Ag}$

are $+1.81 \mathrm{~V},-0.74 \mathrm{~V},+1.50 \mathrm{~V}$ and +0.8 V respectively. Identify two of them which cannot be oxidised by $\left(\mathrm{MnO}_4\right)^{-1} / \mathrm{H}^{+}$

A
a & d
B
a & c
C
b & d
D
b & c
3
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: For strong electrolytes the plot of Molar conductivity versus Concentration gives a straight line with slope equal to +A and intercept equal to $\lambda_{\mathrm{m}}$

Reason: For strong electrolytes, $\lambda_{\mathrm{m}}$ increases slowly with dilution due to increase in the distance between the ions and increase in ionic mobility

A
Assertion is correct but Reason is incorrect.
B
Both Assertion and Reason are incorrect.
C
Assertion is incorrect but Reason is correct.
D
Both Assertion and Reason are correct.
4
COMEDK 2025 Morning Shift
MCQ (Single Correct Answer)
+1
-0
What is the reduction potential of a half-cell consisting of a Pt electrode dipped in $2.2 \mathrm{M} \mathrm{Fe}^{2+}$ and $0.04 \mathrm{M} \mathrm{Fe}^{3+}$ solution where the reaction taking place is conversion of $\mathrm{Fe}^{3+}$ ions to $\mathrm{Fe}^{2+}$ ?

$$\mathrm{E}^0\left(\mathrm{Fe}^{3+} / \mathrm{Fe}^{2+}\right)=0.771 \mathrm{~V}$$

A
0.598 V
B
0.723 V
C
0.668 V
D
0.719 V
COMEDK Subjects
EXAM MAP