Chemistry Outside Delhi Set - 1 2023-2024 Science (English Medium) Class 12 Question Paper Solution

The molar ionic conductivities of \[\ce{Ca^2+}\] and \[\ce{CI-}\] are 119.0 and 76.3 S cm² mol⁻¹ respectively. The value of limiting molar conductivity of \[\ce{CaCl2}\] will be ______.

195.3 S cm² mol⁻¹

43.3 S cm² mol⁻¹

314.3 S cm² mol⁻¹

271.6 S cm² mol⁻¹

Consider the following reaction:

\[\begin{array}{cc}
\ce{H}\phantom{.......}\ce{H}\phantom{..................................}\\
\backslash\phantom{........}\backslash\phantom{...............................}\\
\ce{C = O} + \ce{C = O} + \ce{Conc. KOH ->[\Delta] A +B}\\
/\phantom{........}/\phantom{...............................}\\
\ce{H}\phantom{.......}\ce{H}\phantom{..................................}\\
\end{array}\]

Identify A and B from the given options:

A - Methanol, B - Potassium formate

A - Ethanol, B - Potassium formate

A - Methanal, B - Ethanol

A - Methanol, B - Potassium acetate

Which of the following acids represents Vitamin C?

Saccharic acid 

Gluconic acid

Ascorbic acid

Benzoic acid

Rosenmund reduction is used for the preparation of Aldehydes. The catalyst used in this reaction is ______.

\[\ce{Pd - BaSO4}\]

Anhydrous \[\ce{AlCl3}\]

Iron (III) oxide

\[\ce{HgSO4}\]

Which alkyl halide from the given options will undergo S_N1 reaction faster?

\[\ce{(CH3)3C - Br}\]

\[\ce{(CH3)2CH - Br}\]

\[\ce{CH3 - CH2 - Br}\]

\[\ce{(CH3)3C - CH2 - Br}\]

From the elements of 3d series given below, which element shows the maximum number of oxidation states?

Scandium

Manganese

Chromium

Titanium

The correct Mathematical expression of Arrhenius equation is ______.

k = −Ae^Ea/RT

k = e^Ea/RT

k = Ae^−Ea/RT

k = −Ae^−Ea/RT

Identify the tertiary amine from the following:

\[\begin{array}{cc}
\phantom{..}\ce{CH3}\\
|\\
\ce{CH3 - N - CH3}
\end{array}\]

\[\begin{array}{cc}
\ce{CH3 - CH - CH3}\\
|\phantom{..}\\
\ce{NH}
\end{array}\]

\[\ce{CH3 - NH - CH2 - CH3}\]

\[\ce{(C2H5)2CHNH2}\]

Nucleophilic addition of Grignard reagent to ketones followed by hydrolysis with dilute acids forms ______.

Alkene

Primary alcohol 

Tertiary alcohol

Secondary alcohol

In a given graph of zero-order reaction, the slope and intercept are:

Slope = k, Intercept = [R]₀

Slope = −k, Intercept = [R]₀

Slope = `k/2.303`, Intercept = In[R]₀

Slope = `−k/2.303`, Intercept = In A

Match the reagents required for the given reactions:

I - (r), II - (p), III - (s), IV - (q)

I - (q), II - (r), III - (p), IV - (s)

I - (s), II - (q), III - (p), IV - (r)

I - (p), II - (s), III - (r), IV - (q)

The general electronic configuration of d-block elements is ______.

(n − 1) d¹⁻¹⁰ns¹⁻²

(n − 1) d¹⁰ns¹⁻²

(n − 1) d¹⁰ns²⁻³

(n − 1) d⁰ns¹⁻²

Assertion (A): p-nitrophenol is less acidic than phenol.

Reason (R): Nitro group is electron withdrawing and helps in the stabilisation of p-nitrophenoxide ion.

Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A).

Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of the Assertion (A).

Assertion (A) is true, but Reason (R) is false.

Assertion (A) is false, but Reason (R) is true.

Assertion (A): Benzoic acid does not undergo Friedel-Crafts reaction.

Reason (R): Carboxyl group is deactivating and the catalyst aluminium chloride gets bonded to the carboxyl group.

Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A).

Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of the Assertion (A).

Assertion (A) is true, but Reason (R) is false.

Assertion (A) is false, but Reason (R) is true.

Assertion (A): Fructose is a reducing sugar.

Reason (R): Fructose does not reduce Fehling solution and Tollen’s reagent.

Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A).

Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of the Assertion (A).

Assertion (A) is true, but Reason (R) is false.

Assertion (A) is false, but Reason (R) is true.

Assertion (A): For a Daniell cell, \[\ce{Zn/Zn^2+(1M) || Cu^2+(1M)/Cu}\] with E⁰_cell = 1.1 V, if the external opposing potential is more than 1.1 V, the electrons flow from \[\ce{Cu to Zn}\].

Reason (R): Cell acts like a galvanic cell.

Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A).

Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of the Assertion (A).

Assertion (A) is true, but Reason (R) is false.

Assertion (A) is false, but Reason (R) is true.

Define the following term:

Order of a reaction

Define activation energy.

18 g of a non-volatile solute is dissolved in 200 g of \[\ce{H2O}\] freezes at 272.07 K. Calculate the molecular mass of solute (K_f for water = 1.86 K kg mol⁻¹)

Which compound in the given pair would undergo S_N2 reaction at a faster rate and why?

\[\ce{CH3 - CH2 - I and CH3 - CH2 - Br}\]

Arrange the following compounds in the increasing order of their boiling points:

Butane, 1-Bromobutane, 1-Iodobutane, 1-Chlorobutane 

Write the stepwise mechanism of nucleophilic addition reactions in the carbonyl compounds.

How do you convert the Toluene to Benzoic acid

How will you bring about the following conversion in not more than two steps?

Ethanol to 3-Hydroxybutanal

What happens when glucose reacts with bromine water? Write chemical equation.

Two bases are mentioned below, identify which is present in DNA and which one is present in RNA: 

1. Thymine,
2. Uracil.

Draw the geometrical isomers of complex \[\ce{[Pt(en)2Cl2]^2+}\].

On the basis of crystal field theory, write the electronic configuration for d⁴ ion if ∆₀ < P.

What is meant by unidentate ligand?

Give an example of unidentate ligand.

Calculate emf of the following cell at 25°C:

\[\ce{Sn/Sn^2+ (0.001 M) || H+ (0.01 M) | H2_{(g)} (1 bar) | Pt_{(s)}}\]

Given: \[\ce{E^\circ(Sn^2+/sn) = -0.14 V, E^\circ H+/H2 = 0.00 V (log 10 = 1)}\]

Write chemical equation for the following reaction:

Hydroboration-oxidation reaction

Write chemical equation for the following reaction:

Williamson Synthesis

Write chemical equation for the following reaction:

Friedel-Crafts Alkylation of Anisole

Write the equation involved in the following reaction:

Reimer-Tiemann reaction

Write chemical test to distinguish between the following compounds:

Phenol and Benzoic acid

Propanal and Propanone

Which one of the given compounds is a stronger acid and why?

\[\ce{CH2FCH2CH2COOH or CH3CHFCH2COOH}\]

Explain the following term:

Essential amino acids

Explain the peptide bond.

Explain the following term:

Denaturation

Write the IUPAC name of the given compound:

The presence of \[\ce{-NO2}\] group at ortho or para position increases the reactivity of haloarenes towards nucleophilic substitution reactions. Give reason to explain the above statement.

What happens when ethyl chloride is treated with alcoholic potassium hydroxide? 

Show that the time required for 99.9% completion in a first order reaction is 10 times of half-life (t_1/2) of the reaction [log 2 = 0.3010, log 10 = 1].

The following question is a case-based question. Read the case carefully and answer the questions that follow.

Answer the following questions:

(a) Predict whether \[\ce{[CoF6]^3-}\] is diamagnetic or paramagnetic and why?
[Atomic number: \[\ce{Co}\] = 27]   (1)

(b) What is the coordination number of \[\ce{Co}\] in \[\ce{[Co(en)2Cl2]+}\]?   (1)

(c) (i) Write the IUPAC name of the given complex:   (1)

\[\ce{[Pt(NH3)2Cl2]^2+}\]   

(ii) Explain \[\ce{[Co(NH3)6]^3+}\] is an inner orbital or outer orbital complex.   (1)

                                            OR

(c) Using valence bond theory, deduce the shape and hybridisation of \[\ce{[Ni(NH3)6]^2+}\] [Atomic number of Ni = 28].   (2)

The following question is a case-based question. Read the case carefully and answer the questions that follow.

Answer the following questions:

(a) What is the function of a salt bridge in a galvanic cell?   (1)

(b) When does galvanic cell behave like an electrolytic cell?  (1)

(c) Can copper sulphate solution be stored in a pot made of zinc? Explain with the help of the value of \[\ce{E^0_{cell}}\].  (2)

\[\ce{(E^0 Cu^2+/Cu = 0.34V)}\]

\[\ce{(E^0 Zn^2+/Zn = -0.76V)}\]

                                                 OR

(c) How much charge in terms of Faraday is required for the following:  (2)

1. 1 mol of \[\ce{MnO^-4}\] to \[\ce{Mn^2+}\]
2. 1 mol of \[\ce{H2O}\] to \[\ce{O2}\]

Why Zinc is not regarded as a transition element?

What is Lanthanoid contraction?

Why first ionization enthalpy of chromium is lower than that of zinc?

Why are transition elements good catalysts?

Give reasons for the following:

The transition metals generally form coloured compounds.

Out of \[\ce{KMnO4}\] and \[\ce{K2MnO4}\], which one is paramagnetic and why?

Complete the following ionic equation:

\[\ce{Cr2O^2-_7 + 14H+ + 6e- ->}\]

Define reverse osmosis.

Why are aquatic species more comfortable in cold water in comparison to warm water?

A solution containing 2 g of glucose (M = 180 g mol⁻¹) in 100 g of water is prepared at 303 K. If the vapour pressure of pure water at 303 K is 32.8 mm Hg, what would be the vapour pressure of the solution? 

Predict whether Van't Hoff factor will be less or greater than one, when Ethanoic acid is dissolved in benzene.

Define the term: 

Ideal solution

Calculate the mass of \[\ce{CaCl2}\] (molar mass = 111 g mol⁻¹) to be dissolved in 500 g of water to lower its freezing point by 2K, assuming that \[\ce{CaCl2}\] undergoes complete dissociation.

(K_f for water = 1.86 K kg mol⁻¹)

An amide ‘A’ with molecular formula \[\ce{C7H7ON}\] undergoes Hoffmann Bromamide degradation reaction to give amine ‘B’. 'B’ on treatment with nitrous acid at 273-278 K form ‘C’ and on treatment with chloroform and ethanolic potassium hydroxide forms 'D’. ‘C’ on treatment, with ethanol gives ‘E’. Identify ‘A’, ‘B’, ‘C’ ‘D’ and ‘E' and write the sequence of chemical equations.

What is Hinsberg's reagent?

Arrange the following compounds in the increasing order of their basic strength in gaseous phase:

\[\ce{C2H5NH2, (C2H5)3N, (C2H5)2NH}\]

Give reason for the following:

Methyl amine is more basic than aniline.

Give reason for the following:

Aniline readily reacts with bromine water to give 2, 4, 6-tribromoaniline.

Give reason for the following:

Primary amines have higher boiling point than tertiary amines.