Chemistry Delhi Set 2 2016-2017 Commerce (English Medium) Class 12 Question Paper Solution

Write one similarity between Physisorption and Chemisorption

Write the structure of 2,4-dinitrochlorobenzene

For a reaction R ---> P, half-life (t_1/2) is observed to be independent of the initial concentration of reactants. What is the order of reaction?

Write the IUPAC name of the following compound and classify it as primary, secondary and tertiary amine.

CH₃NHCH(CH₃)₂

Primary

Secondary

Tertiary

Write the formula of an oxo-anion of Chromium (Cr) in which it shows the oxidation state equal to its group number

Calculate the degree of dissociation (α) of acetic acid if its molar conductivity (Λ_m) is 39.05 S cm² mol⁻¹.

Given λ^°(H⁺) = 349.6 S cm² mol⁻¹ and λ^°(CH₃COO⁻) = 40.9 S cm² mol⁻¹

Draw the structures of `H_3PO_2`

Draw the structures of the following molecules: XeF₄

Define the term: 

Ideal solution

Define Molarity (M).

Complete chemical reactions are:Cl₂ + H₂O →

Complete the following reactions : XeF₆ + 3H₂O →

What happens when conc. is H₂SO₄ added to Cu? Write the equations.

What happens when SO₃ is passed through water? Write the equations.

Write the reactions involved Hell-Volhard Zelinsky reaction?

Write the reactions involved Decarboxylation reaction

Write one difference in Lyophobic sol and Lyophilic sol

Write one difference in Solution and Colloid

Write one difference in Homogeneous catalysis and Heterogeneous catalysis

Following compounds are given to you :

2-Bromopentane, 2-Bromo-2-methylbutane, 1-Bromopentane

1) Write the compound which is most reactive towards S_N2 reaction.

2) Write the compound which is optically active.

3)  Write the compound which is most reactive towards β-elimination reaction. 

Outline the principles of refining of metals by the following methods:  Vapour phase refining

What is the principle behind the zone refining of metals?

What is meant by the term “chromatography”?

A 10% solution (by mass) of sucrose in water has freezing point of 269.15 K. Calculate the freezing point of 10% glucose in water, if freezing point of pure water is 273.15 K

Given : (Molar mass of sucrose = 342 g mol⁻¹)

(Molar mass of glucose = 180 g mol⁻¹)

Explain the following term with a suitable example:

Cationic detergents

Define the following : Narrow spectrum antibiotics

Define the following : Disinfectants

Calculate the mass of Ag deposited at cathode when a current of 2 amperes was passed through a solution of AgNO₃ for 15 minutes.

(Given : Molar mass of Ag = 108 g mol⁻¹ lF = 96500 C mol⁻¹)

Define terms: Fuel cell

What type of isomerism is shown by the complex [Co(NH₃)₆] [Cr(CN)₆]?

Why a solution of [Ni(H₂O)₆]²⁺ is green while a solution of [Ni(CN)₄]²⁻ is colourless? (At. no. of Ni = 28)

Write the IUPAC name of the following complex : [Co(NH₃)₅(CO₃)]Cl.

Write structures of compounds A, B and C in of the following reactions

Write structures of compounds A, B and C in of the following reactions

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

Benzoic acid to Benzaldehyde

Do the following conversions in not more than two steps :

Ethyl benzene to Benzoic acid

Do the following conversions in not more than two steps :

Propanone to Propene

Write the name of monomers used for getting the following polymers : Neoprene

Write the structures of the monomers used for getting the following polymers

Melamine – formaldehyde polymer

Write the names and structures of the monomers of the following polymers: Buna-S

Following data are obtained for reaction :

N₂O₅ → 2NO₂ + 1/2O₂

1) Show that it follows first order reaction.

2) Calculate the half-life.

(Given log 2 = 0.3010, log 4 = 0.6021)

Give reasons  Acetylation of aniline reduces its activation effect.

Give reasons CH₃NH₂ is more basic than C₆H₅NH₂.

Give reasons  Although –NH₂ is o/p directing group, yet aniline on nitration gives a significant amount of m-nitroaniline

Give reasons Thermal stability decreases from H₂O to H₂Te.

Give reasons Fluoride ion has higher hydration enthalpy than chloride ion.

Nitrogen does not form pentahalide.

After watching a programme on TV about the presence of carcinogens (cancer causing agents) Potassium bromate and Potassium iodate in bread and other bakery products, Ritu a class XII student decided to aware others about the adverse effects of these carcinogens in foods. She consultanted the school principal and requested him to instruct canteen contractor to stop selling sandwiches, pizza, burgers and other bakery products to the students. Principal took an immediate action and instructed the canteen contractor to replace the bakery products with some proteins and vitamins rich food like fruits, salads, sprouts etc. The decision was welcomed by the parents and students.

After reading the above passage, answer the following questions:

1) What are the values (at least two) displayed by Ritu?

2) Which polysaccharide component of carbohydrates is commonly present in bread?

3) Write the two types of secondary structure of proteins.

4) Give two examples of water soluble vitamins.

Write the product(s) in the following reactions

Write the product(s) in the following reactions

Write the product(s) in the following reaction

Give simple chemical tests to distinguish between the following pairs of compounds :

Ethanol and phenol

Give simple chemical tests to distinguish between the following pairs of compounds :

Propanol and 2-methylpropan-2-ol

Write the formula of reagents used in the following reactions :

Bromination of phenol to 2,4,6-tribromophenol

Write the formula of reagents used in the following reactions :

Hydroboration of propene and then oxidation to propanol.

Arrange the following compound groups in the increasing order of their property indicated :

p-nitrophenol, ethanol, phenol (acidic character)

Arrange the following compound groups in the increasing order of their property indicated :

Propanol, Propane, Propanal (boiling point)

Write the mechanism (using curved arrow notation) of the following reaction :

How would you account for the following: Transition metals form complex compounds.

Give an example and suggest a reason for the following feature of the transition metal chemistry:

The lowest oxide of transition metal is basic, the highest is amphoteric/acidic.

Account for the following:

E° value for the Mn³⁺/Mn²⁺ couple is highly positive (+1.57 V) as compare to Cr³⁺/Cr²⁺.

Write one similarity and one difference between the chemistry of lanthanoid and actinoid elements.

How is the variability in oxidation states of transition metals different from that of the non-transition metals? Illustrate with examples.

Explain why Cu⁺ ion is not stable in aqueous solutions?

Orange colour of `Cr_2O_7^(2–)` ion changes to yellow when treated with an alkali. Why?

How would you account for the following:

The chemistry of actinoids is more complicated as compared to lanthanoids.

An element has atomic mass 93 g mol^–1 and density 11.5 g cm^–3. If the edge length of its unit cell is 300 pm, identify the type of unit cell

Write any two differences between amorphous solids and crystalline solids

Calculate the number of unit cells in 8.1 g of aluminium if it crystallizes in a f.c.c. structure. (Atomic mass of Al = 27 g mol^–1)

Give reasons : In stoichiometric defects, NaCl exhibits Schottky defect and not Frenkel defect.

Give reasons : Silicon on doping with Phosphorous forms n-type semiconductor.

Give reasons:Ferrimagnetic substances show better magnetism than antiferromagnetic substances.