1
COMEDK 2023 Evening Shift
MCQ (Single Correct Answer)
+1
-0

The rate constant for a First order reaction at $$560 \mathrm{~K}$$ is $$1.5 \times 10^{-6}$$ per second. If the reaction is allowed to take place for 20 hours, what percentage of the initial concentration would have converted to products?

A
11.14
B
10.23
C
12.46
D
21.2
2
COMEDK 2023 Evening Shift
MCQ (Single Correct Answer)
+1
-0

What would be the final product [$$\mathbf{X}$$] formed when p-Toluidine undergoes the following series of reactions?

$$\begin{aligned} & \text { P-Toluidine } \xrightarrow[\text { Pyridine }]{\left\{\mathrm{CH}_2, \mathrm{CO}_2 \mathrm{O}\right.}[\mathrm{P}] \\ & {[\mathrm{P}] \xrightarrow{\mathrm{Br}_2 / \mathrm{CH}_3 \mathrm{COOH}}[\mathrm{O}]} \\ & {[\mathrm{Q}] \xrightarrow[\Delta]{\text { dilŠ½G }}[\mathrm{R}]} \\ & {\mathrm{[R]} \xrightarrow[0^{\circ} \mathrm{C}]{\mathrm{Nan}_2 / \mathrm{HCl}}\mathrm{[S]}} \\ & {[\mathrm{S}] \xrightarrow{\mathrm{H}_2 \mathrm{PO}_2}[\mathrm{X}]} \\ \end{aligned}$$

A
COMEDK 2023 Evening Shift Chemistry - Compounds Containing Nitrogen Question 6 English Option 1
B
COMEDK 2023 Evening Shift Chemistry - Compounds Containing Nitrogen Question 6 English Option 2
C
COMEDK 2023 Evening Shift Chemistry - Compounds Containing Nitrogen Question 6 English Option 3
D
COMEDK 2023 Evening Shift Chemistry - Compounds Containing Nitrogen Question 6 English Option 4
3
COMEDK 2023 Evening Shift
MCQ (Single Correct Answer)
+1
-0

The energy of an electron in the ground state of Hydrogen atom is $$-2.18 \times 10^{-18} \mathrm{~J}$$. What would be the energy associated with the second excited state of $$\mathrm{Li}$$ ?

A
$$ -2.18 \times 10^{-18} \mathrm{~J} $$
B
$$ -4.905 \times 10^{-18} \mathrm{~J} $$
C
$$ -0.242 \times 10^{-18} \mathrm{~J} $$
D
$$ -3.26 \times 10^{-18} \mathrm{~J} $$
4
COMEDK 2023 Evening Shift
MCQ (Single Correct Answer)
+1
-0

Identify the incorrect statement.

A
Ability of Fluorine to stabilise higher oxidation states in transition metals is due to the low lattice enthalpy of the fluorides.
B
The second and third Ionisation enthalpies of $$\mathrm{Mn}^{2+}$$ and $$\mathrm{Fe}^{3+}$$ respectively have lower values than expected.
C
Transition metals readily form alloys because their metallic radii are within about $$15 \%$$ of each other.
D
$$\mathrm{Cr}^{2+}$$ acts as reducing agent while $$\mathrm{Mn}^{3+}$$ acts as an oxidising agent though both the ions have $$\mathrm{d}^4$$ configuration.
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