Share
Notifications

View all notifications
Advertisement

Chemistry (Theory) 2014-2015 ISC (Science) Class 12 Question Paper Solution

Login
Create free account


      Forgot password?
Chemistry (Theory)
Marks: 70Academic Year: 2014-2015
Date: March 2015

Question 1 is Compulsory

Answer Any 2 Question From Question 2 to Question 4

Answer Any 2 From Question 5 to Question 7

Answer Any 2 From Question 8 to Question 10


[20]1
[5]1.1 | Fill in the blanks by choosing the appropriate word/word from those ·given in the brackets:  (increases, decreases, positive, efficient, 68, non-efficient, no a-hydrogen, α-hydrogen, negative, Rosenmund's, greater, Cannizzaro, 74, common-ion effect, lesser; buffer action, diamagnetic, paramagnetic)
[1]1.1.1

The more _____ the standard reduction potential of a metal, the ____ is its ability to displace hydrogen from acids.

Concept: Galvanic Cells, Mechanism of Current Production in a Galvanic Cell; - Standard Hydrogen Electrode
Chapter: [6.02] Galvanic cells, mechanism of current production in a galvanic cell;
[1]1.1.2

Both ccp and hcp are _________ packings and occupy. about_______ % of the available space.

Concept: States of Matters: Structure and Properties Solid State - Packing in 3 – D
Chapter: [0.02] States of Matters: Structure and Properties Solid State
[1]1.1.3

The solubility of silver chloride _______ in the presence of sodium: chloride because of ___________

Concept: Solubility Product and Its Applications - Solubility product
Chapter: [5.05] Solubility product and its applications
[1]1.1.4

Benzaldehyde undergoes ________ reaction on treatment with concentrated sodium hydroxide because it has _______ atom

Concept: Haloalkanes - Reaction of Haloalkanes with - Aq. Sodium Hydroxide
Chapter: [11.03] Preparation, properties, uses of haloalkanes
[1]1.1.5

The transition metals show _________ character because of the presence of unpaired· electrons and Cu+ is ____________ because of its electronic configuration is [Ar]3d10

Concept: General Properties of the Transition Elements (D-block)
Chapter: [0.1] Chemistry of Transition and Inner-Transition Elements: d-Block: 3d, 4d and 5d series f-Block: 4f and 5f series
[5]1.2 | Complete the · following statements by selecting the correct alternative from the choices are given:
[1]1.2.1

The molal freezing point constant of water is 1·86 K kg mol-1. Therefore, the freezing point of 0·1 M NaCl solution in water is expected to be:

1) -1.86°C

2) -0.372 °C

3) -0.186 °C

4) +0.372 °C

Concept: Relative Molecular Mass of Non-volatile Substances - Freezing Point Depression
Chapter: [1.03] Relative molecular mass of non-volatile substances
[1]1.2.2

For a first-order reaction, the rate constant for decomposition of `N_2O_5` is `6 xx 10^(-4) sec^(-1)`.The half-life period for the decomposition in seconds is:

1) 11·55

2) 115·5

3) 1155

4) 1·155

Concept: Order of a Reaction - Mathematical Derivation of Rate Equation for First Order Reaction
Chapter: [3.01] Order of a reaction
[1]1.2.3

When acetaldehyde is treated With Grignard reagent, followed by hydrolysiS-the product formed is:

1) Primary alcohol

2) Secondary alcohol

3) Carboxylic acid

4) Tertiary alcohol

Concept: Acid Derivatives - Reaction with Grignard Reagent
Chapter: [14.02] Acid derivatives
[1]1.2.4

The geometry of XeF6 molecule and_ the hybridization of Xe atom in the molecule.is:

1) Distorted octahedral and `sp^3d^3`

2) Square planar and `sp^3d^2`

3) Pyramidal and `sp^3`

4)Octahedral and `sp^3d^3`

Concept: Hybridization, Shape and Structure of Compounds
Chapter: [0.08] Chemistry of p-Block Elements: Group 16, 17, 18
[1]1.2.5

In the complexes `[Fe(CN)_6]^(3-)` and `[pt(en) (H_2O)_2(NO_2 (Cl)^(2+)]``the respective oxidation numbers of central metal atoms are

1) +3 and +4

2) +6 and + 4

3) +6 and +3

4) +3 and + 3

Concept: Crystal Lattices and Unit Cells - Introduction
Chapter: [0.02] States of Matters: Structure and Properties Solid State
[5]1.3 | Answer the following questions:
[1]1.3.1

What is the effect of temperature on the ionic, product of water? How will it change the pH value of a neutral solution?

Concept: Chemical Kinetics - Effect of Temperature on the Rate Constant of a Reaction
Chapter: [3.04] Effect of temperature on the rate constant of a reaction
[1]1.3.2

How many hours does it take to reduce 3 moles of `Fe^(3+)`to `Fe^(2+)` with 2.0 A Current intensity?

Concept: Normality, Molality - Simple Problems Relating Mass, Molar Mass and Mole
Chapter: [1.05] Normality, molality
[1]1.3.3

How is urea prepared by Wohler synthesis?

Concept: Acid Derivatives - Urea Preparation (By Wohler'S Synthesis)
Chapter: [14.02] Acid derivatives
[1]1.3.4

Two liquids A and B form type II non-ideal solution which shows a minimum in its temperature -mole fraction plot (T -x diagram). Can the two liquids be completely separated by fractional distillation?

Concept: Normality, Molality - Normality, Molality, Molarity, Mole Fraction, as Measures of Concentration
Chapter: [1.05] Normality, molality
[1]1.3.5

The aqueous solution of sodium acetate is basic. Explain.

Concept: Ionization of Acids and Bases - Common Ion Effect in the Ionization of Acids and Bases
Chapter: [5.07] Common ion effect
[5]1.4

Match the following:

1 Disaccharide a Lucas reagent
2 Carbylamine b Condensation polymer
3 Dacron c Obnoxious smell
4 Low spin complex `d^2sp^3` d Sucrose
5 Anhydrous `ZnCl_2 + conc.HCl` e Hexaamminecobalt(III)ion

 

Concept: Cyanides, Isocyanides and Nitro Compounds
Chapter: [0.15] Cyanides, Isocyanides, Nitro compounds, Amines and Diazonium Salt
[10]2
[5]2.1
[1]2.1.1

A solution containing 0·5 g of KCl dissolves in 100 g of water and freezes at -0·24°C. Calculate the degree of dissociation of the salt. (Kf for water= 1.86 °C) Atomic weights [K = 39, Cl = 35·5]

Concept: Normality, Molality - Simple Problems Relating Mass, Molar Mass and Mole
Chapter: [1.05] Normality, molality
[1]2.1.2

If 1·71 g of sugar (molar mass = 342) are dissolved in 500 ml of an aqueous solution at 300 K, what will be its osmotic pressure?

Concept: Relative Molecular Mass of Non-volatile Substances - Osmotic Pressure and Its Application in the Determination of Relative Molecular Mass
Chapter: [1.03] Relative molecular mass of non-volatile substances
[1]2.1.3

0·70g of an organic compound, when dissolved in 32g of acetone, produces an elevation of 0·25°C in the boiling point. Calculate the molecular mass of the organic compound (Kb for acetone = 1·72 K kg `mol^(-1)`).

Concept: Relative Molecular Mass of Non-volatile Substances - Boiling Point Elevation
Chapter: [1.03] Relative molecular mass of non-volatile substances
[4]2.2
Advertisement
[2]2.2.1

What is the difference between the order of a reaction and the molecularity of a reaction?

Concept: Order of a Reaction - Order-reaction (Meaning)
Chapter: [3.01] Order of a reaction
[2]2.2.2

A substance decomposes by following first order kinetics. If 50% of the compound is decomposed in 120 minutes, how long will it take for 90% of the compound to decompose?

Concept: Order of a Reaction - Problems Based on First Order Rate Equation and Half Life Period
Chapter: [3.01] Order of a reaction
[1]2.3

Name the crystal structure of the copper metal.

Concept: Coordination Compounds - Magnetic Characteristics of Coordination Compounds on the Basis of Valence Bond Theory and Crystal Field Theory
Chapter: [0.07] Coordination Compounds
[10]3
[6]3.1
[2]3.1.1

Chromium metal crystallises with a body centred cubic lattice. The edge length of the unit cell is found to be 287 pm. Calculate the atomic radius: What would be the density of chromium in g/cm3? (atomic mass of Cr = 52 ·99)

Concept: States of Matters: Structure and Properties Solid State - Calculation of the Number of Atoms per Unit Cell
Chapter: [0.02] States of Matters: Structure and Properties Solid State
[1]3.1.2

Why does sodium chloride on heating with sodium vapours acquire yellow colour?

Concept: Amorphous and Crystalline Solids
Chapter: [0.02] States of Matters: Structure and Properties Solid State
[1]3.1.3

The equilibrium constant for the reaction: 

`N_(2(g)) + 3H_(2(g)) ⇌ 2NH_(3(g)) at 715 K, is 6.0 xx 10^(-2)`

If, in a particular reaction, there ate 0·25 mol L-1 of H2. and 0·06 mol L-1 of NH3 present, calculate the concentration of N2 at equilibrium

Concept: Reversible Reactions and Dynamic Equilibrium - Equilibrium Constant in Terms of Partial Pressures Kp
Chapter: [4.01] Reversible reactions and dynamic equilibrium
[1]3.1.4

Calculate the concentration of OH- ions in solution when [H+] = 6.2 x 10-2L mol L-1.

Concept: Chemical Kinetics - Effect of Concentration of Reactants on the Rate of a Reaction
Chapter: [3.1] Effect of concentration of reactants on the rate of a reaction
[1]3.1.5

State the Le Chatelier's principle.

Concept: Le Chatelier’S Principle and Its Applications to Chemical Equilibria - Le Chatelier’s Principle
Chapter: [4.02] Le Chatelier’s Principle and its applications to chemical equilibria
[2]3.2

For a crystal of sodium chloride, state:

1) The type of lattice in which it crystallises

2) The coordina~ion number of each sodium ion and chloride ion in the crystal lattice.

3) The number of sodium ions and chloride ions present in a unit cell of sodium chloride.

4) The structural arrangement of the sodium chloride crystaL

Concept: Crystal Lattices and Unit Cells - Introduction
Chapter: [0.02] States of Matters: Structure and Properties Solid State
[2]3.3

Consider the following reaction:

`N_2O_(4(g)) + Heat ⇌ 2NO_(2(g))`

How is the Composition of equilibrium mixture affected by:

1) a change in temperature

2) a change in pressure

3) change in concentration of N2O4

Concept: Reversible Reactions and Dynamic Equilibrium - Characteristics of Equilibrium Constant
Chapter: [4.01] Reversible reactions and dynamic equilibrium
[10]4
[3]4.1

The specific conductance of a 0.01 M solution of acetic acid at +98 K is 1.65 x 10-4 ohm cm-1. The molar conductance at infinite dilution for H+ ion and CH3COO- ion is 349.1 ohm-1 cm2mol-1 and 40.9 ohm-1 cm2mol-1 respectively.

Calculate:

1) Molar conductance of the solution.

2) The degree of dissociation of CH3COOH.

3) A dissociation constant for acetic acid

Concept: Electrolytic Conductance - Measuring of Molar and Equivalent Conductance
Chapter: [6.04] Electrolytic conductance [6.04] Electrolytic conductance
[4]4.2
[2]4.2.1

Calculate the e.m.f of the following cell reaction at 298 K:

`Mg_(s) + Cu^(2+) (0.0001 M) -> Mg^(2+) (0.0001M) + Cu_(s)`

The standard potential `(E^@)`of the cell is  2.71 V

Concept: Galvanic Cells, Mechanism of Current Production in a Galvanic Cell; - Mechanism of Production of Electric Current in a Galvanic Cell
Chapter: [6.02] Galvanic cells, mechanism of current production in a galvanic cell;
[2]4.2.2

The solubility product (Ksp) of BaSO4 is 1.5 X 10-9.Calculate the solubility of barium sulphate in pure water and in 0.1 M BaCl2.

Concept: Solubility - Solubility of a Gas in a Liquid
Chapter: [1.01] Raoult's law and colligative properties
[3]4.3 | Explain the following :
[2]4.3.1

When NH4 Cl and NH4OH are added to a solution containing both, Fe3+ and Ca2+ ions, which ion is precipitated first and why?

Concept: Ionic Equilibria - Buffer Solutions
Chapter: [5.04] Buffer solutions
[1]4.3.2

Dissociation of H2S is suppressed in acidic medium.

Concept: General Properties of the Transition Elements (D-block)
Chapter: [0.1] Chemistry of Transition and Inner-Transition Elements: d-Block: 3d, 4d and 5d series f-Block: 4f and 5f series
[5]5
[1]5.1

Write the IUPAC names of the following coordination compounds: 

[Cr(NH3)4(H2O)2]Cl3

Concept: Definitions of Some Important Terms Pertaining to Coordination Compounds
Chapter: [0.07] Coordination Compounds

Write the IUPAC names of the following coordination compounds:

`[PtCl_2(NH_3)_4][PtCl_4]`

Concept: Definitions of Some Important Terms Pertaining to Coordination Compounds
Chapter: [0.07] Coordination Compounds
[1]5.2

State the hybridization and magnetic property of [Fe(CN)6]3- ion according to the valence bond theory.

Concept: Coordination Compounds - Magnetic Characteristics of Coordination Compounds on the Basis of Valence Bond Theory and Crystal Field Theory
Chapter: [0.07] Coordination Compounds
[3]5.3
[2]5.3.1

What type of isomers are `[Co(NH_3)_5Br]SO_4`and `[Co(NH_3)_5SO_4]Br`?. Give a  chemical test to distinguish between them.

Concept: Isomerism in Coordination Compounds - Stereoisomerism
Chapter: [0.07] Coordination Compounds
[1]5.3.2

Write the structures of optical isomers of the complex ion `[Co(en)_2Cl_2]^+`

Concept: Isomerism in Coordination Compounds - Stereoisomerism
Chapter: [0.07] Coordination Compounds
Advertisement
[5]6
[3]6.1

Give balanced chemical equations for Fluorine is passed through cold, dilute NaOH solution

Concept: P - Block Group 17 Elements - Reaction of Fluorine
Chapter: [0.08] Chemistry of p-Block Elements: Group 16, 17, 18

Give balanced chemical equations for  Hydrogen peroxide is treated with an acidified KMnO4 solution.

Concept: Ozone - Hydrogen Peroxide
Chapter: [0.09] Preparation/ Manufacture, Properties and Uses of Compounds of Groups 16, 17, – Ozone, Sulphur Dioxide, Sulphuric Acid, Hydrochloric Acid

Give balanced chemical equations for Sulphuric acid is treated with hydrogen sulphide

Concept: P - Block Group 16 Elements - Sulphuric Acid
Chapter: [0.08] Chemistry of p-Block Elements: Group 16, 17, 18 [0.09] Preparation/ Manufacture, Properties and Uses of Compounds of Groups 16, 17, – Ozone, Sulphur Dioxide, Sulphuric Acid, Hydrochloric Acid
[2]6.2

Draw the structure of xenon tetrafluoride molecule and state the hybridization of the central atom and the geometry of the molecule.

Concept: P - Block Group 18 Elements - Formation of Xenon Compounds with Fluorine and Oxygen – Equation
Chapter: [0.08] Chemistry of p-Block Elements: Group 16, 17, 18
[5]7
[3]7.1

Name the important ore of silver. Write all the steps and reactions involved in the Cyanide process for the extraction of silver from its ore.

Concept: Cyanides, Isocyanides and Nitro Compounds
Chapter: [0.15] Cyanides, Isocyanides, Nitro compounds, Amines and Diazonium Salt
[2]7.2 | Explain the following:

Why do transition metal ions possess a great tendency to form complexes?

Concept: General Properties of the Transition Elements (D-block)
Chapter: [0.1] Chemistry of Transition and Inner-Transition Elements: d-Block: 3d, 4d and 5d series f-Block: 4f and 5f series

The paramagnetic character in-3d-transition series elements increases-: up to Mn and then decreases.

Concept: General Properties of the Transition Elements (D-block)
Chapter: [0.1] Chemistry of Transition and Inner-Transition Elements: d-Block: 3d, 4d and 5d series f-Block: 4f and 5f series
[10]8
[5]8.1
[1]8.1.1

How can the following conversions be brought about

Glycerol to formic acid

Concept: Carboxylic Acids - Uses of formic acid and acetic acid
Chapter: [14.01] Carboxylic acids
[1]8.1.2

How can the following conversions be brought about:

Chlorobenzene to phenol

Concept: Carboxylic Acids - Uses of formic acid and acetic acid
Chapter: [14.01] Carboxylic acids
[1]8.1.3

How can the following conversions be brought about:

Diethyl ether to ethanol

Concept: Ethers - Physical and Chemical Properties of ether
Chapter: [13.02] Ethers
[2]8.1.4

How can the following conversions be brought about:

Phenol to aniline.

Concept: Acid Derivatives - Acetylation of Ethanol and Aniline
Chapter: [14.02] Acid derivatives
[2]8.2
[1]8.2.1

How is iodoform prepared from ethanol? Give balanced equation.

Concept: Preparation, Properties, and Uses of the Following: Ethyl Bromide, Chloroform, Iodoform, Haloform Reaction
Chapter: [11.05] Preparation, properties, and uses of the following
[1]8.2.2

What.will be the product fonned when chlorobenzene is heated with sodium metal in the presence of dry ether?

Concept: Alcohols, Phenols and Ethers - Nomenclature
Chapter: [12.04] Classification, general formulae, structure and nomenclature [13.02] Ethers
[3]8.3

Identify the compounds A, B, C, D, E, and F:

\[\ce{CH3COCH3->[Conc.HNO3][(O)]A}\]

\[\ce{->[SOCl2]B}\]

\[\ce{->[NH3]C}\]

\[\ce{->[LiAlH4]D}\]

\[\ce{->[HNO2]E}\]

\[\ce{->[CH3COCl]F}\]

Concept: Nomenclature of Coordination Compounds - Naming of Mononuclear Coordination Compounds
Chapter: [0.07] Coordination Compounds
[10]9
[3]9.1

Write the equations involved in the following reactions : Reimer – Tiemann reaction

Concept: Chemical Reactions of Phenols (Only)
Chapter: [12.03] Distinction between primary, secondary and tertiary alcohols

Write the chemical equations to illustrate the following name reactions : Rosenmund reduction

Concept: Aldehydes and Ketones - Preparation of Aldehydes
Chapter: [14.02] Acid derivatives

Give ba1anced equations for the following name reactions:

Hoffmann’s degradation reaction

Concept: Acid Derivatives - Hoffmann’s Degradation
Chapter: [14.02] Acid derivatives
[3]9.2

Give of chemical test to distinguish between the following pairs of compounds:

Ethylamine and diethylamine

Concept: Isocyanides - Methods of preparation From primary amines
Chapter: [0.15] Cyanides, Isocyanides, Nitro compounds, Amines and Diazonium Salt

Give one chemical test to distinguish between the following pairs of compounds

Acetaldehyde and benzaldehyde

Concept: Uses of Aldehydes and Ketones
Chapter: [13.01] Carbonyl compounds
[4]9.3
[2]9.3.1

Arrange the following compounds in the ascending order of their basic strength and give reasons for your answer:

Methylamine, Aniline, Ethylamine, Diethyl ether

Concept: Acid Derivatives - Acetylation of Ethanol and Aniline
Chapter: [14.02] Acid derivatives
[2]9.3.2

Name the monomers and the type of polymerization in each of the following polymers:

Polyester

Concept: Polymers - Polymerisation
Chapter: [0.16] Polymers

Name the monomers and the type of polymerization in each of the following polymers:

Bakelite

Concept: Types of Polymerisation Reactions - Condensation Polymerisation Or Step Growth Polymerisation
Chapter: [0.16] Polymers
[10]10
[3]10.1

An organic compound A with molecular formula C2H7N on reaction with nitrous acid gives a compound B. Bon controlled oxidation gives compound C. C reduces Tollen's -reagent to give silver mirror and D. B reacts with D in the presence of concentrated sulphuric acid to give sweet smelling compound E. Identify A, B, C, D. and E. Give the reaction of C with ammonia

Concept: Aniline - Importance in Synthesis of Other Organic Compounds
Chapter: [0.15] Cyanides, Isocyanides, Nitro compounds, Amines and Diazonium Salt
[4]10.2

Give balanced equations for the following reactions:

How.will you Convert ethylamine to methylamine?

Concept: Nitro Compounds - Methods of Preparation Nitro Compounds from Primary Amines
Chapter: [0.15] Cyanides, Isocyanides, Nitro compounds, Amines and Diazonium Salt

Give balanced equations for the following reaction:

What is the effect of denaturation on the structure of proteins?·

Concept: Introduction of Proteins
Chapter: [0.17] Biomolecules – carbohydrates, proteins, enzymes, vitamins and nucleic acids

Give balanced equations for the following reactions:

Name the nitrogen base residues present in DNA

Concept: Introduction of Nucleic Acids
Chapter: [0.17] Biomolecules – carbohydrates, proteins, enzymes, vitamins and nucleic acids
[3]10.3

Give balanced equations for the following reactions:

Aniline is treated with nitrous acid and HCl at the low temperature

Concept: Chlorobenzene - Preparation from Aniline
Chapter: [11.04] Chlorobenzene

Give balanced equations for the following reactions:

Acetyl chloride is treated with ethyl alcohol.

Concept: Acid Derivatives - Acetylation of Alcohol, Ammonia and Amines
Chapter: [14.02] Acid derivatives

Give balanced equations for the following reactions:

Formaldehyde is treated with ammonia.

Concept: Aldehydes and Ketones - Reactions with Ammonia, Hydroxylamine, Hydrazine and Phenyl Hydrazine
Chapter: [13.01] Carbonyl compounds
Advertisement

Request Question Paper

If you dont find a question paper, kindly write to us





      View All Requests

Submit Question Paper

Help us maintain new question papers on Shaalaa.com, so we can continue to help students




only jpg, png and pdf files

CISCE previous year question papers Class 12 Chemistry (Theory) with solutions 2014 - 2015

     CISCE Class 12 Chemistry (Theory) question paper solution is key to score more marks in final exams. Students who have used our past year paper solution have significantly improved in speed and boosted their confidence to solve any question in the examination. Our CISCE Class 12 Chemistry (Theory) question paper 2015 serve as a catalyst to prepare for your Chemistry (Theory) board examination.
     Previous year Question paper for CISCE Class 12 Chemistry (Theory)-2015 is solved by experts. Solved question papers gives you the chance to check yourself after your mock test.
     By referring the question paper Solutions for Chemistry (Theory), you can scale your preparation level and work on your weak areas. It will also help the candidates in developing the time-management skills. Practice makes perfect, and there is no better way to practice than to attempt previous year question paper solutions of CISCE Class 12.

How CISCE Class 12 Question Paper solutions Help Students ?
• Question paper solutions for Chemistry (Theory) will helps students to prepare for exam.
• Question paper with answer will boost students confidence in exam time and also give you an idea About the important questions and topics to be prepared for the board exam.
• For finding solution of question papers no need to refer so multiple sources like textbook or guides.
Advertisement
View in app×