Science (English Medium)
Academic Year: 2023-2024
Date & Time: 27th February 2024, 10:30 am
Duration: 3h
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GENERAL INSTRUCTIONS:
Read the following instructions carefully and follow them:
- This question paper contains 33 questions. All questions are compulsory.
- Question paper is divided into FIVE sections - Section A, B, C, D and E.
- Section A - question number 1 to 16 are multiple choice type questions. Each question carries 1 mark.
- Section B - question number 17 to 21 are very short answer type questions. Each question carries 2 marks.
- Section C - question number 22 to 28 are short answer type questions. Each question carries 3 marks.
- Section D - question number 29 and 30 are case-based questions. Each question carries 4 marks.
- Section E - question number 31 to 33 are long answer type questions. Each question carries 5 marks.
- There is no overall choice given in the question paper. However, an internal choice has been provided in few questions in all the Sections except section A.
- Kindly note that there is a separate question paper for Visually Impaired candidates.
- Use of calculator is NOT allowed.
The molar ionic conductivities of \[\ce{Mg^2+}\] and \[\ce{SO^2-_4}\] are 106.0 S cm2 mol−1 and 160.0 S cm2 mol−1 respectively. The value of limiting molar conductivity of \[\ce{MgSO}\], will be ______.
266 S cm2 mol−1
622 S cm2 mol−1
288 S cm2 mol−1
822 S cm2 mol−1
Chapter:
From the elements of 3d series given below, which element shows the maximum number of oxidation states?
Scandium
Manganese
Chromium
Titanium
Chapter:
Which alkyl halide from the given options will undergo SN1 reaction faster?
\[\ce{(CH3)3C - Br}\]
\[\ce{(CH3)2CH - Br}\]
\[\ce{CH3 - CH2 - Br}\]
\[\ce{(CH3)3C - CH2 - Br}\]
Chapter:
Which of the following acids represents Vitamin C?
Saccharic acid
Gluconic acid
Ascorbic acid
Benzoic acid
Chapter:
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
\[\ce{HgSO4}\]
Chapter:
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
Chapter:
In effective collisions the colliding molecules must have ______.
Proper orientation only.
A certain minimum amount of activation energy.
Threshold energy only.
Threshold energy and proper orientation both.
Chapter:
Identify the secondary amine from the given options:
\[\ce{(CH3)2CHNH2}\]
\[\ce{CH3NHCH(CH3)2}\]
\[\ce{(CH3)3CNH2}\]
\[\ce{CH3(CH2)2NH2}\]
Chapter:
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
Chapter:
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
Chapter:
Nucleophilic addition of Grignard reagent to ketones followed by hydrolysis with dilute acids forms ______.
Alkene
Primary alcohol
Tertiary alcohol
Secondary alcohol
Chapter:
Match the reagents required for the given reactions:
| I. | Oxidation of primary alcohols to aldehydes | (p) | \[\ce{NaBH4}\] |
| II. | Butan-2-one to Butan-2-ol | (q) | 85% phosphoric acid at 440 K |
| III. | Bromination of Phenol to 2, 4, 6-Tribromophenol | (r) | PCC |
| IV. | Dehydration of propan-2-ol propene | (s) | Bromine water |
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)
Chapter:
Assertion (A): Bromination of Phenol can be carried out even in the absence of Lewis acid.
Reason (R): \[\ce{-OH}\] group of Phenol has the high activation effect.
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.
Chapter:
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.
Chapter:
Assertion (A): For a Daniell cell, \[\ce{Zn/Zn^2+(1M) || Cu^2+(1M)/Cu}\] with E0cell = 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.
Chapter:
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.
Chapter:
Calculate the molar mass of a compound when 6.3 g of it is dissolved in 27 g of chloroform to form a solution that has a boiling point of 68.04°C. The boiling point of pure chloroform is 61.04°C and Kb for chloroform is 3.63°C kg mol −1.
Chapter:
Which of the following compounds will react more rapidly by SN2 reaction & why?
\[\begin{array}{cc}
\phantom{....}\ce{CH3}\\
\phantom{..}|\\
\ce{CH3 - C - Br}\\
\phantom{..}|\\
\phantom{....}\ce{CH3}\\
\end{array}\]
or
\[\begin{array}{cc}
\ce{CH3 - CH2 - CH - CH3}\\
\phantom{......}|\\
\phantom{.......}\ce{Br}\\
\end{array}\]
Chapter:
Arrange the following compounds in the increasing order of their boiling points:
\[\ce{CH3CH2CH2CH2Br,}\]
\[\begin{array}{cc}
\ce{CH3}\phantom{...................}\\
\backslash\phantom{...............}\\
\ce{CH - CH2Br,}\\
/\phantom{...............}\\
\ce{CH3}\phantom{...................}
\end{array}\]
\[\begin{array}{cc}
\phantom{...}\ce{CH3}\\
\phantom{}|\\
\ce{CH3 - C - CH3}\\
\phantom{}|\\
\phantom{..}\ce{Br}
\end{array}\]
Chapter:
Write the stepwise mechanism of nucleophilic addition reactions in the carbonyl compounds.
Chapter:
How do you convert the Toluene to Benzoic acid
Chapter: [0.08] Aldehydes, Ketones and Carboxylic Acids
How will you bring about the following conversion in not more than two steps?
Ethanol to 3-Hydroxybutanal
Chapter: [0.08] Aldehydes, Ketones and Carboxylic Acids
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What happens when Glucose reacts with HI? Write chemical equation.
Chapter:
Which type of bond holds a DNA double helix together?
Chapter:
Draw the geometrical isomers of complex \[\ce{[Co(en)2Cl2]+}\].
Chapter: [0.05] Coordination Compounds
On the basis of Crystal Field Theory, write the electronic configuration of d4 ion if Δ0 > P.
Chapter: [0.05] Coordination Compounds
What is meant by didentate ligand?
Chapter: [0.05] Coordination Compounds
Write chemical test to distinguish between the following compounds:
Phenol and Benzoic acid
Chapter: [0.08] Aldehydes, Ketones and Carboxylic Acids
Propanal and Propanone
Chapter: [0.08] Aldehydes, Ketones and Carboxylic Acids
Which one of the given compounds is a stronger acid and why?
\[\ce{CH2FCH2CH2COOH or CH3CHFCH2COOH}\]
Chapter:
Show that the time required for 99.9% completion in a first order reaction is 10 times of half-life (t1/2) of the reaction [log 2 = 0.3010, log 10 = 1].
Chapter:
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: \[\ce{E^\circ(Sn^2+/sn) = -0.14 V, E^\circ H+/H2 = 0.00 V (log 10 = 1)}\]
Chapter: [0.02] Electrochemistry
Define the following term:
Non-essential amino acids
Chapter:
Define the following term:
Anomers
Chapter: [0.05] Coordination Compounds
Why are haloalkanes more reactive towards nucleophilic substitution reactions than haloarenes?
Chapter:
What happens when ethyl chloride is treated with aqueous KOH?
Chapter: [0.06] Haloalkanes and Haloarenes
Write chemical equation for the following reaction:
Hydroboration-oxidation reaction
Chapter:
Write chemical equation for the following reaction:
Williamson Synthesis
Chapter:
Write chemical equation for the following reaction:
Friedel-Crafts Alkylation of Anisole
Chapter:
Write the equation involved in the following reaction:
Reimer-Tiemann reaction
Chapter: [0.07] Alcohols, Phenols and Ethers
The following question is a case-based question. Read the case carefully and answer the questions that follow.
|
In a galvanic cell, chemical energy of a redox reaction is converted into electrical energy, whereas in an electrolytic cell the redox reaction occurs on passing electricity. The simplest galvanic cell is in which \[\ce{Zn}\] rod is placed in a solution of \[\ce{ZnSO4}\] and \[\ce{Cu}\] rod is placed in a solution of \[\ce{CuSO4}\]. The two rods are connected by a metallic wire through a voltmeter. The two solutions are joined by a salt bridge. The difference between the two electrode potentials of the two electrodes is known as electromotive force. In the process of electrolysis, the decomposition of a substance takes place by passing an electric current. One mole of electric charge when passed through a cell will discharge half a mole of a divalent metal ion such as \[\ce{Cu^2+}\]. This was first formulated by Faraday in the form of laws of electrolysis. |
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 mol of \[\ce{MnO^-4}\] to \[\ce{Mn^2+}\]
- 1 mol of \[\ce{H2O}\] to \[\ce{O2}\]
Chapter:
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The following question is a case-based question. Read the case carefully and answer the questions that follow.
| The nature of bonding, structure of the coordination compound can be explained to some extent by valence bond theory. The central metal atom/ion makes available a number of vacant orbitals equal to its coordination number. The appropriate atomic orbitals (s, p and d) of the metal hybridise to give a set of equivalent orbitals of definite geometry such as square planar, tetrahedral, octahedral and so on. A strong covalent bond is formed only when the orbitals overlap to the maximum extent. The d-orbitals involved in the hybridisation may be either inner d-orbitals i.e. (n − 1) d or outer d-orbitals i.e. nd. The complexes formed are called inner orbital complex (low spin complex) and outer orbital complex (high spin complex) respectively. Further, the complexes can be paramagnetic or diamagnetic in nature. The drawbacks of this theory are that this involves number of assumptions and also does not explain the colour of the complex. |
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)
Chapter:
Why are aquatic species more comfortable in cold water in comparison to warm water?
Chapter: [0.01] Solutions
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?
Chapter:
Predict whether Van't Hoff factor will be less or greater than one, when Ethanoic acid is dissolved in benzene.
Chapter:
Define the term:
Ideal solution
Chapter: [0.01] Solutions
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.
(Kf for water = 1.86 K kg mol−1)
Chapter:
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.
Chapter:
Arrange the following compounds in the increasing order of their basic strength in gaseous phase:
\[\ce{C2H5NH2, (C2H5)3N, (C2H5)2NH}\]
Chapter:
Give reason for the following:
Methyl amine is more basic than aniline.
Chapter:
Give reason for the following:
Aniline readily reacts with bromine water to give 2, 4, 6-tribromoaniline.
Chapter:
Give reason for the following:
Primary amines have higher boiling point than tertiary amines.
Chapter: [0.09] Amines
Why Zinc is not regarded as a transition element?
Chapter:
What is Lanthanoid contraction?
Chapter: [0.04] d-block and f-block Elements
Why first ionization enthalpy of chromium is lower than that of zinc?
Chapter:
Give reasons for the following:
The transition metals generally form coloured compounds.
Chapter: [0.04] d-block and f-block Elements
Out of \[\ce{KMnO4}\] and \[\ce{K2MnO4}\], which one is paramagnetic and why?
Chapter:
Complete the following ionic equation:
\[\ce{Cr2O^2-_7 + 14H+ + 6e- ->}\]
Chapter:
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