1
COMEDK 2024 Evening Shift
MCQ (Single Correct Answer)
+1
-0

Given that the freezing point of benzene is $$5.48^{\circ} \mathrm{C}$$ and its $$\mathrm{K}_{\mathrm{f}}$$ value is $$5.12{ }^{\circ} \mathrm{C} / \mathrm{m}$$. What would be the freezing point of a solution of $$20 \mathrm{~g}$$ of propane in $$400 \mathrm{~g}$$ of benzene?

A
$$-0.34^{\circ} \mathrm{C}$$
B
$$-0.17^{\circ} \mathrm{C}$$
C
$$-5.8^{\circ} \mathrm{C}$$
D
$$-0.2{ }^{\circ} \mathrm{C}$$
2
COMEDK 2024 Evening Shift
MCQ (Single Correct Answer)
+1
-0

Identify the final product formed when Benzamide undergoes the following reactions:

COMEDK 2024 Evening Shift Chemistry - Carboxylic Acids and Its Derivatives Question 1 English

A
Acetanilide
B
Acetophenone
C
Aniline
D
Benzoic acid
3
COMEDK 2024 Evening Shift
MCQ (Single Correct Answer)
+1
-0

Identify the correct statement regarding corrosion of iron rod left exposed to atmosphere.

A

The reaction occurring at the cathodic area is:

$$ \mathrm{O}_2(\mathrm{~g})+2 \mathrm{H}_2 \mathrm{O}(\mathrm{l})+4 \mathrm{e} \rightarrow 4 \mathrm{OH}^{-} $$

B

The reaction occurring at the cathodic area is:

$$ \mathrm{O}_2(\mathrm{~g})+4 \mathrm{H}^{+}(\mathrm{aq})+4 \mathrm{e} \rightarrow 2 \mathrm{H}_2 \mathrm{O}(\mathrm{l}) ; \mathrm{E}^0=+1.23 \mathrm{~V} $$

C

Reaction occurring at anodic area is:

$$ 2 \mathrm{H}_2 \mathrm{O}(\mathrm{l}) \rightarrow \mathrm{O}_2(\mathrm{~g})+4 \mathrm{H}^{+}+4 \mathrm{e} $$

D

The overall reaction occurring during the corrosion process is:

$$ 2 \mathrm{Fe}_{(\mathrm{S})}+3 / 2 \mathrm{O}_2(\mathrm{~g})+6 \mathrm{H}^{+} \rightarrow 2 \mathrm{Fe}^{3+}+3 \mathrm{H}_2 \mathrm{O} ; \mathrm{E}^0=-1.23 \mathrm{~V} $$

4
COMEDK 2024 Evening Shift
MCQ (Single Correct Answer)
+1
-0

Two statements, Assertion and Reason are given below. Choose the correct option.

Assertion: n-propyl tert-butyl ether can be readily prepared in the laboratory by Williamson's synthesis.

Reason: The reaction occurs by $$\mathrm{S}_{\mathrm{N}} 1$$ attack of Primary alkoxide on Tert-alkyl halide to give good yield of the product, n-propyl tert-butyl ether.

A
Assertion is incorrect bur reason is correct.
B
Both Assertion and Reason are correct and Reason is the correct explanation for Assertion.
C
Assertion is correct but Reason is incorrect.
D
Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion.
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