1
COMEDK 2025 Morning Shift
MCQ (Single Correct Answer)
+1
-0
The conductivity of 0.01 M solution of $\mathrm{CH}_3 \mathrm{COOH}$ at 298 K is $1.65 \times 10^{-4} \mathrm{Scm}^{-1}$ What is the $\mathrm{pK}_{\mathrm{a}}$ value of the acid if $\lambda^0\left(\mathrm{H}^{+}\right)$and $\lambda^0\left(\mathrm{CH}_3 \mathrm{COO}\right)^{-1}$ are $349.1 \mathrm{Scm}^2 \mathrm{~mol}^{-1}$ and $40.9 \mathrm{Scm}^2 \mathrm{~mol}^{-1}$ respectively?
A
4.73
B
1.87
C
3.47
D
2.95
2
COMEDK 2024 Evening Shift
MCQ (Single Correct Answer)
+1
-0

What volume of $$0.2 \mathrm{~M}$$ Acetic acid is to be added to $$100 \mathrm{ml}$$ of $$0.4 \mathrm{M}$$ Sodium acetate so that a Buffer solution of $$\mathrm{pH}$$ equal to 4.94 is obtained? $$(\mathrm{pK}_{\mathrm{a}}$$ of $$\mathrm{CH}_3 \mathrm{COOH}=4.76)$$

A
132.1 ml
B
125.3 ml
C
150.2 ml
D
110.6 ml
3
COMEDK 2024 Afternoon Shift
MCQ (Single Correct Answer)
+1
-0

$$ 1 \mathrm{~cm}^3 \text { of } 0.01 \mathrm{~M} \mathrm{~HCl} \text { is added to } 1 \mathrm{~L} \text { of } \mathrm{NaCl} \text { solution. The } \mathrm{pH} \text { of the resulting solution is: } $$

A
5
B
3
C
1
D
2
4
COMEDK 2024 Morning Shift
MCQ (Single Correct Answer)
+1
-0

$$\mathrm{A}_3 \mathrm{~B}_4$$ is a sparingly soluble salt with a solubility of $$\mathrm{s} g / \mathrm{L}$$. If the Molar mass of $$\mathrm{A}_3 \mathrm{~B}_4$$ is $$\mathrm{Mg} / \mathrm{mol}$$, what is the expression for its $$\mathrm{K}_{\text {sp }}$$ ?

A
$$6912(\mathrm{~s} / \mathrm{M})^7$$
B
$$8413(\mathrm{~s} \mathrm{M})^8$$
C
$$5184(\mathrm{~s} / \mathrm{M})^7$$
D
$$5185(\mathrm{~s} \mathrm{M})^6$$
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