1
COMEDK 2025 Evening Shift
MCQ (Single Correct Answer)
+1
-0
An aqueous solution of an electrolyte $\mathrm{A}_3 \mathrm{~B}$ is prepared by dissolving 0.5625 g in 750 ml of water and is found to be $80 \%$ ionised. If $\mathrm{K}_{\mathrm{b}}$ for water is $0.52 \mathrm{~K} \mathrm{~kg} \mathrm{~mol}^{-1}$, calculate the boiling point of the solution at 1.0 atm pressure.
A
374.33 K
B
371.68 K
C
373.18 K
D
377.2 K
2
COMEDK 2025 Evening Shift
MCQ (Single Correct Answer)
+1
-0

Arrange the complex ions in the increasing order of their magnetic moments

A. $\left[\mathrm{Fe}\left(\mathrm{H}_2 \mathrm{O}\right)_6\right]^{2+}$
B. $\left[\mathrm{Fe}(\mathrm{CN})_6\right]^{4-}$
C. $\left[\mathrm{Fe}(\mathrm{CN})_6\right]^{3-}$
D. $\left[\mathrm{FeF}_6\right]^{3-}$

A
$\mathrm{D}<\mathrm{A}<\mathrm{B}<\mathrm{C}$
B
$\mathrm{B}<\mathrm{C}<\mathrm{A}<\mathrm{D}$
C
$\mathrm{D}<\mathrm{C}<\mathrm{B}<\mathrm{A}$
D
$\mathrm{A}<\mathrm{D}<\mathrm{C}<\mathrm{B}$
3
COMEDK 2025 Evening Shift
MCQ (Single Correct Answer)
+1
-0
When the temperature of a reaction $\mathrm{A}+\mathrm{B} \rightarrow \mathrm{C}$ is increased from 300 K to 310 K the rate constant increases by $12 \%$. What is the Activation energy of the reaction?
A
$163.9 \mathrm{~kJ} / \mathrm{mol}$
B
$85.69 \mathrm{~kJ} / \mathrm{mol}$
C
$192.17 \mathrm{~kJ} / \mathrm{mol}$
D
$8.76 \mathrm{~kJ} / \mathrm{mol}$
4
COMEDK 2025 Evening Shift
MCQ (Single Correct Answer)
+1
-0
The first electron gain enthalpy of oxygen is $-141 \mathrm{~kJ} \mathrm{~mol}^{-1}$, its second electron gain enthalpy is :
A
A positive value
B
Less negative value than the first
C
Maximum negative value than the first
D
Same value as that of the first
EXAM MAP