List of practice Questions

Given below are two statements: One is labelled as Assertion A and the other is labelled as Reason R.

Assertion A: H₂Te is more acidic than H₂S.

Reason R: Bond dissociation enthalpy of H₂Te is lower than H₂S.

In light of the above statements, choose the most appropriate from the options given below:

Which of the following reactions are disproportionation reactions?
$\text{(A) } \text{Cu}^+ \rightarrow \text{Cu}^{2+} + \text{Cu}$
$\text{(B) } 3\text{MnO}_4^{2-} + 4\text{H}^+ \rightarrow 2\text{MnO}_4^- + \text{MnO}_2 + 2\text{H}_2\text{O}$
$\text{(C) } 2\text{KMnO}_4 \rightarrow \text{K}_2\text{MnO}_4 + \text{MnO}_2 + \text{O}_2$
$\text{(D) } 2\text{MnO}_4^- + 3\text{Mn}^{2+} + 2\text{H}_2\text{O} \rightarrow 5\text{MnO}_2 + 4\text{H}^+$
Choose the correct answer from the options given below.

Major product of the following reaction is

Identify the name reaction

Consider the following reaction: $ \text{MnO}_2 + \text{KOH} + \text{O}_2 \rightarrow \text{A} + \text{H}_2\text{O} $. Product ‘A’ in neutral or acidic medium disproportionates to give products ‘B’ and ‘C’ along with water. The sum of spin-only magnetic moment values of B and C is _________ BM (nearest integer).
(Given atomic number of Mn is 25)

Consider the above chemical reaction. Product "A" is:

The major products formed:

A and B respectively are:

Identify the product A in the following reaction.

Match List-I with the List-II

List-I Reaction	List-II Type of redox reaction
(A) N₂(g) + O₂(g) → 2NO(g)	(I) Decomposition
(B) 2Pb (NO₃)₂(s) → 2PbO(s) + 4NO₂(g) + O₂(g)	(II) Displacement
(C) 2Na(s) + 2H₂O(l) → 2NaOH(aq) + H₂(g)	(III) Disproportionation
(D) 2NO₂(g) + 2OH^-(aq) → NO₂^-(aq) + NO₃^-(aq) + H₂O(l)	(IV) Combination

Choose the correct answer from the options given below:

(a) Upper half of a convex lens is covered with a black paper. Draw a ray diagram to show the formation of image of an object placed at a distance of 2F from such a lens. Mention the position and nature of the image formed. State the observable difference in the image obtained if the lens is uncovered. Give reason to justify your answer.
(b) An object is placed at a distance of 30 cm from the optical centre of a concave lens of focal length 15 cm. Use lens formula to determine the distance of the image from the optical centre of the lens.

$\textbf{Reduction potential of ions are given below:}$
\[ \begin{array}{ccc} \text{ClO}_4^- & \text{IO}_4^- & \text{BrO}_4^- \\ E^\circ = 1.19 \, \text{V} & E^\circ = 1.65 \, \text{V} & E^\circ = 1.74 \, \text{V} \\ \end{array} \]
The correct order of their oxidising power is:

$\textbf{Choose the correct statements about the hydrides of group 15 elements.}$
A. The stability of the hydrides decreases in the order $\text{NH}_3 > \text{PH}_3 > \text{AsH}_3 > \text{SbH}_3 > \text{BiH}_3$
B. The reducing ability of the hydrides increases in the order $\text{NH}_3 < \text{PH}_3 < \text{AsH}_3 < \text{SbH}_3 < \text{BiH}_3$
C. Among the hydrides, $\text{NH}_3$ is a strong reducing agent while $\text{BiH}_3$ is a mild reducing agent.
D. The basicity of the hydrides increases in the order $\text{NH}_3 < \text{PH}_3 < \text{AsH}_3 < \text{SbH}_3 < \text{BiH}_3$
Choose the most appropriate from the option given below:

The number of oxygen atoms present in chemical formula of fuming sulphuric acid is _______.

Identify the correct statements about p-block elements and their compounds.
(A) Non metals have higher electronegativity than metals.
(B) Non metals have lower ionisation enthalpy than metals.
(C) Compounds formed between highly reactive nonmetals and highly reactive metals are generally ionic.
(D) The non-metal oxides are generally basic in nature.
(E) The metal oxides are generally acidic or neutral in nature.

Suggest any two measures to solve the problem of ‘land degradation’.

Using integration, find the area bounded by the ellipse $ 9x^2 + 25y^2 = 225 $, the lines $ x = -2, x = 2 $, and the X-axis.

A single-phase half-controlled bridge converter supplies an inductive load with ripple-free load current. The triggering angle of the converter is $ 60^\circ $. The ratio of the rms value of the fundamental component of the input current to the rms value of the total input current of the bridge is (rounded off to 3 decimal places).

In the DC–DC converter shown in the figure, the current through the inductor is continuous. The switching frequency is $500\,\text{Hz}$.

The output voltage $V_o$ across the load is assumed to be constant and ripple-free.

The peak value of the inductor current (in amperes) is __________ (rounded off to the nearest integer).

A dielectric slab of dielectric constant $ K $ and thickness $ t $ is inserted between plates of a parallel plate capacitor of plate separation $ d $ and plate area $ A $. Obtain an expression for its capacitance.

A capacitor of capacitance 100 μF is charged to a potential of 12 V and connected to a 6.4 mH inductor to produce oscillations. The maximum current in the circuit would be:

Statement-I : Aniline on reaction with concentrated $H_2SO_4$ at 475 K gives p-amino benzene sulphonic acid. This gives blood red colour with Lassaigne’s test.
Statement-II : Aniline forms a salt with anhydrus $AlCl_3$ in Friedel Craft’s reaction.

Identify A and B in the following reaction sequence.

The azo-dye (Y) formed in the following reactions is: Sulphanilic acid + NaNO$_2$ + CH$_3$COOH → X

Given below are two statements:
Statement I: Aniline reacts with con. $ H_2SO_4 $ followed by heating at 453–473 K gives p-aminobenzene sulphonic acid, which gives blood red colour in the 'Lassaigne's test'.
Statement II: In Friedel-Craft's alkylation and acylation reactions, aniline forms salt with the $ AlCl_3 $ catalyst. Due to this, nitrogen of aniline acquires a positive charge and acts as a deactivating group.
In the light of the above statements, choose the correct answer from the options given below:

A compound ($ x $) with molar mass $ 108 \, \text{g mol}^{-1} $ undergoes acetylation to give a product with molar mass $ 192 \, \text{g mol}^{-1} $. The number of amino groups in the compound ($ x $) is ______.