Chemistry (Theory) 2016-2017 ISC (Commerce) Class 12 Question Paper Solution

Fill in the blanks by choosing the appropriate word/words from those given in the brackets:

(iodoform, acetaldehyde, positive, greater, acidic, acetone, disaccharide, negative, increases, glucose, decreases, chloroform, polysaccharide, lactose, lesser, basic, cationic hydrolysis, anionic hydrolysis)

Calcium acetate on heating gives ________ which gives _______ on heating with iodine and sodium hydroxide solution.

Fill in the blanks by choosing the appropriate word/words from those given in the brackets: 

(iodoform, acetaldehyde, positive, greater, acidic, acetone, disaccharide, negative, increases, glucose, decreases, chloroform, polysaccharide, lactose, lesser, basic, cationic hydrolysis, anionic hydrolysis)

On dilution of a solution, its specific conductance ________ while its equivalent conductance ________.

Fill in the blanks by choosing the appropriate word/words from those given in the brackets:  

(iodoform, acetaldehyde, positive, greater, acidic, acetone, disaccharide, negative, increases, glucose, decreases, chloroform, polysaccharide, lactose, lesser, basic, cationic hydrolysis, anionic hydrolysis)

Sucrose is a _________ and yields upon hydrolysis, a mixture of ________ and fructose.

Fill in the blanks by choosing the appropriate word/words from those given in the brackets:  

(iodoform, acetaldehyde, positive, greater, acidic, acetone, disaccharide, negative, increases, glucose, decreases, chloroform, polysaccharide, lactose, lesser, basic, cationic hydrolysis, anionic hydrolysis)

More _______ the standard reduction potential of a substance, the ______ is its ability to displace hydrogen from acids.

Fill in the blanks by choosing the appropriate word/words from those given in the brackets: 

(iodoform, acetaldehyde, positive, greater, acidic, acetone, disaccharide, negative, increases, glucose, decreases, chloroform, polysaccharide, lactose, lesser, basic, cationic hydrolysis, anionic hydrolysis)

An aqueous solution of CH₃COONa is ________ due to ______.

Complete the following statement by selecting the correct alternative from the choices given: 

In a face-centered cubic lattice, atom (A) occupies the comer positions and atom (B) occupies the face centre positions. If one atom of (B) is missing from one of the face-centered points, the formula of the compound is:

A₂B₅

A₂B₃

AB₂

A₂B

The half-life period of a first-order reaction is 20 minutes. The time required for the concentration of the reactant to change from 0.16 M to 0.02 M is ______.

80 minutes

60 minutes

40 minutes

20 minutes

Complete the following statement by selecting the correct alternative from the choices given:  

For a spontaneous reaction ΔG° and E° cell will be respectively:

-ve and +ve

+ve and -ve

+ve and +ve

-ve and -ve

Complete the following statement by selecting the correct alternative from the choices given:  

The conjugate acid of `"HPO"_4^(2-)` is : 

H₃PO₃ 

H₃PO₄ 

`"H"_2"PO"_4^-`

`"PO"_4^(3-)`

Complete the following statement by selecting the correct alternative from the choices given:  

The polymer formed by the condensation of hexamethylenediamine and adipic acid is: 

Teflon

Bakelite

Dacron

Nylon-66

Why the freezing point depression (ΔT_f) of 0.4 M NaCl solution is nearly twice than that of 0.4 M glucose solution?

Identify the order of reaction from the following unit of rate constant (k): 

mol L⁻¹ sec⁻¹

Identify the order of reaction from the following unit for its rate constant:

L mol^–1 s^–1

Specific conductivity of 0.20 M solution of KCl at 298 K is 0.025 S cm⁻¹. Calculate its molar conductivity.

Name the order of reaction which proceeds with a uniform rate throughout. 

Answer the following question:

What are the products formed when phenol and nitrobenzene are treated separately with a mixture of concentrated sulphuric acid and concentrated nitric acid?

Match the following: 

Determine the freezing point of a solution containing 0.625 g of glucose (C₆H₁₂O₆) dissolved in 102.8 g of water. 

(Freezing point of water = 273 K, K_f for water = 1.87 K kg mol⁻¹, at. wt. C = 12, H = 1, O = 16)

A 0.15 M aqueous solution of KCl exerts an osmotic pressure of 6.8 atm at 310 K. Calculate the degree of dissociation of KCl. (R = 0.0821 L atm K⁻¹ mol⁻¹). 

A solution containing 8.44 g of sucrose in 100 g of water has a vapour pressure 4.56 mm of Hg at 273 K. If the vapour pressure of pure water is 4.58 mm of Hg at the same temperature, calculate the molecular weight of sucrose. 

When ammonium chloride and ammonium hydroxide are added to a solution containing both Al³⁺ and Ca²⁺ ions, which ion is precipitated first and why?

A solution of potassium chloride has no effect on litmus whereas, a solution of zinc chloride turns the blue litmus red. Give a reason.

How many sodium ions and chloride ions are present in a unit cell of sodium chloride crystal?

Lead sulphide has a face-centred cubic crystal structure. If the edge length of the unit cell of lead sulphide is 495 pm, calculate the density of the crystal. 
(Atomic weight of Pb = 207, S = 32)

For the reaction: \[\ce{2H2 + 2NO <=> 2H2O + N2}\], the following rate data was obtained: 

Calculate the following:

1. The overall order of a reaction.
2. The rate law.
3. The value of rate constant (k).

The following electrochemical cell is set up at 298 K:

\[\ce{Zn | Zn^{2+}_{ (aq)} (1 M) || Cu^{2+}_{ (aq)} (1 M) | Cu}\]

Given: \[\ce{E^{\circ}_{Zn^{2+}/Zn}}\] = −0.761 V, \[\ce{E^{\circ}_{Cu^{2+}/Cu}}\] = +0.339 V

Write the cell reaction.

The following electrochemical cell is set up at 298 K: 

\[\ce{Zn | Zn^{2+}_{ (aq)} (1 M) || Cu^{2+}_{ (aq)} (1 M) | Cu}\]

Given: \[\ce{E^{\circ}_{Zn^{2+}/Zn}}\] = −0.761 V, \[\ce{E^{\circ}_{Cu^{2+}/Cu}}\] = +0.339 V

Calculate the emf and free energy change at 298 K.

What is the effect of temperature on the ionic product of water (K_w)?

What happens to the ionic product of water (K_w) if some acid is added to it?

Frenkel defect does not change the density of the ionic crystal whereas Schottky defect lowers the density of ionic crystal. Give a reason.

Name the law or principle to which the following observation confirm:

When water is added to a 1.0 M aqueous solution of acetic acid, the number of hydrogen ion (H⁺) increases.

Name the law or principle to which the following observations confirm:

When 9650 coulombs of electricity is passed through a solution of copper sulphate, 3.175 g of copper is deposited on the cathode (at. wt. of Cu = 63.5).

Name the law or principle to which the following observations confirm: 

When ammonium chloride is added to a solution of ammonium hydroxide, the concentration of hydroxyl ion decreases. 

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

Explain why high pressure is required in the manufacture of sulphur trioxide by the contact process. State the law or principle used. 

Calculate the equilibrium constant (K_c) for the formation of NH₃ in the following reaction: 

\[\ce{N2_{(g)} + 3H2_{(g)} <=> 2NH3_{(g)}}\]

At equilibrium, the concentration of NH₃, H₂ and N₂ are 1.2 × 10⁻², 3.0 × 10⁻² and 1.5 × 10⁻² M respectively.

Explain the following:  

Hydrolysis of ester (ethyl acetate) begins slowly but becomes fast after some time. 

Explain the following:

The pH value of acetic acid increases on the addition of a few drops of sodium acetate. 

Using IUPAC norms write the formulae for Potassium trioxalatoaluminate(III)

Write the formula of the following compound:

Hexaaquairon (II) sulphate

Name the type of isomerism shown by the following compounds:

[Cu(NH₃)₄][PtCl₄] and [Pt(NH₃)₄][CuCl₄]

Name the type of isomerism shown by the following compounds: 

[Co(Pn)₂Cl₂]⁺ and [Co(en)₂Cl₂]⁺ 

For the coordination complex ion [Co(NH₃)₆]³⁺ :

Give the IUPAC name of the complexion.

For the coordination complex ion [Co(NH₃)₆]³⁺:

What is the oxidation number of cobalt in the complexion?

For the coordination complex ion [Co(NH₃)₆]³⁺:

State the type of hybridisation of the complex ion.

For the coordination complex ion [Co(NH₃)₆]³⁺:

State the magnetic nature of the complex.

Give balanced equation for the following reaction: 

Potassium permanganate is heated with concentrated hydrochloric acid.

Give balanced equation for the following reaction: 

Lead sulphide is heated with hydrogen peroxide. 

Give a balanced equation for the following reaction:

Ozone is treated with potassium iodide solution. 

Discuss the theory involved in the manufacture of sulphuric acid by the contact process.

What is the type of hybridisation of iodine in interhalogen compound IF₃?

Draw the structure of xenon hexafluoride (XeF₆) molecule and state the hybridisation of the central atom.

Give the balanced equations for the conversion of argentite (Ag₂S) to metallic silver. 

How can the following conversion be brought about: 

Acetaldehyde to propan-2-ol.

How can the following conversion be brought about:

Nitrobenzene to p-aminoazobenzene.

How can the following conversion be brought about:

Acetic acid to methylamine.

How can the following conversion be brought about:

Aniline to benzene

How will you distinguish between primary, secondary and tertiary amines by Hinsberg’s test? 

Why do alcohols possess higher boiling points as compared to those of corresponding alkanes?

Give balanced equations for the following reaction :

Methyl magnesium bromide with ethyl alcohol. 

Identify the compounds A, B and C: 

\[\ce{C6H5COOH ->[PCl5] A ->[H2 - Pd/BaSO4] B ->[KCN alc.][distil.] C}\]

Identify the compounds A, B and C :

\[\ce{H - C ≡ C - H ->[H2O][dil.H2SO4 + HgSO4] A ->[H2][(Nil)] B ->[140°][cone. H2SO4] C}\]

Give balanced equation for the following name reaction: 

Friedel-Crafts reaction (alkylation)

Give balance equation for the following name reaction:

Williamson’s synthesis

Give a balanced equation for the following name reaction: 

Aldol condensation

Give the chemical test to distinguish:

Ethyl alcohol and sec-propyl alcohol

Give the chemical test to distinguish:

Acetaldehyde and acetic acid

Deficiency of which vitamin causes the following diseases of Scurvy.

Deficiency of which vitamin causes the following diseases of Night blindness

Write two differences between globular and fibrous proteins.

An aliphatic unsaturated hydrocarbon (A) when treated with HgSO₄/H₂SO₄ yields a compound (B) having molecular formula C₃H₆O. (B) on oxidation with concentrated HNO₃ gives two compounds (C) and (D). Compound (C), when treated with PCl₅, gives compound (E). (E) when reacts with ethanol gives a sweet-smelling liquid (F). Compound (F) is also formed when (C) reacts with ethanol in the presence of concentrated H₂SO₄.

(i) Identify the compounds A, B, C, D, E and F.
(ii) Give the chemical equation for the reaction of (C) with chlorine in the presence of red phosphorus and name the reaction.

What is the common name of the polymer obtained by the polymerization of caprolactam? Is it an addition polymer or condensation polymer? 

Answer the following:

Name the two organic compounds which have the same molecular formula C2H6O. Will they react with PCl5? If they react, what are the products formed?

Give balanced equations for the following reaction :

Methyl magnesium bromide with ethyl alcohol. 

Give balanced equations for the following reactions:

Acetic anhydride with phosphorus pentachloride.

Give balanced equations for the following reaction:

Acetaldehyde with hydroxylamine.