CBSE Class 12 Chemistry Question Paper 2019 with Solutions

Question 2)

Arrange the following in increasing order of boiling points :

Question 3)

Why are medicines more effective in colloidal state?

Question 4)

What is difference between an emulsion and a gel?

Question 5)

Define ambidient nucleophile with an example.

Question 6)

What is the basic structural difference between glucose and fructose?

Question 7)

Write the products obtained after hydrolysis of lactose.

Question 8)

Write balanced chemical equations for the following processes :

1. XeF₂ undergoes hydrolysis.
2. MnO₂ is heated with conc. HCl.

Question 9)

Arrange the following in order of property indicated for each set :

1. H₂O, H₂S, H₂Se, H₂Te – increasing acidic character
2. HF, HCl, HBr, HI – decreasing bond enthalpy

Question 10)

State Raoult’s law for a solution containing volatile components. Write two characteristics of the solution which obeys Raoult’s law at all concentrations.

Question 11)

For a reaction

the proposed mechanism is as given below :

(i) Write rate law for the reaction

(ii) Write the overall order of reaction.

(iii) Out of steps a and 2, which one rate determining step?

Question 12)

(i) What is the role of activated charcoal in gas mask?

(ii) A colloidal sol is prepared by the given method in the figure.What is the charge on hydrated ferric oxide collodial particles formed in the test tube? How is the sol represented?

(iii) How does chemisorption vary with temperature?

Question 13)

An element crystallizes in fcc lattice with cell edge of 300 pm. The density of element is . Calculate the number of atoms in 108g of the element.

Question 14)

(a) Name the method of refining which is

(i) used to obtain semiconductor of high purity

(ii) used to obtain low boiling point

(b) Write chemical reactions taking place in the extraction of copper from .

Question 15)

Give reasons for the following:

(i) Transition elements and their compounds act as catalysts.

(ii) value for is negative whereas for is positive.

(iii) Actinoids shows irregularities in their electronic confriguration.

Question 16)

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

(i) Nylon - 6,6

(ii) Glyptal

(iii) Buna - S

Question 17)

(i) Is a homopolymer or copolymer?Give reasons.

(ii) Write monomers of the following polymers:

(iii) What is the role of Sulphur in vulcanization of rubber?

Question 18)

(i) What type of drug is used in sleeping pills?

(ii) What type of detergents are used in toothpaste?

(iii) Why the use of alitame as artificial sweetner is not recommended?

Question 19)

Define the following terms with a suitable example in each:

(i) Broad - spectrum antibiotics

(ii) Disinfectants

(iii) Cationic detergents

Question 20)

(i) Out of and , which one is more reactive towards and why?

(ii) Write the product formed when p-nitrochlorobenzene is heated with aqueous NaOH at 443K followed by acidification?

(iii) Why dextro and laevo - rotatory isomers of butan - 2-ol are difficult to seprate by fractional distillation?

Question 21)

An aromatic compound 'A' on heating with and KOH forms compound 'B' of molecular formula which on reacting with and alcoholic KOH produces a foul smelling compound 'C'. Write the structures and IUPAC names of compound A,B and C.

Question 22)

(i)

(ii)

(iii)

Question 23)

Write chemical equations for the following reactions:

(i) Propane is treated with dilute .

(ii) Acetophenone is treated with .

(iii) Benzoyl chloride is hydrogenated in presence of .

Question 24)

Differentiate between the following:

(i) Amylose and Amylopectin

(ii) Peptide linkage and Glycosidic linkage

(iii) Fibrous proteins and Globular proteins

Question 25)

Write chemical reactions to show that open structure D-glucose contains the following:

(i) Straight chain

(ii) Five alcohol groups

(iii) Aldehyde as carbonyl group

Question 26)

for the given redox reaction is 2.71 V.

Calculate for the reaction. Write the direction of flow of current when external opposite potential is applied us:

(i) less than 2.71V

(ii) greater than 2.71V

Question 27)

(a) Steady current of 2 amperes was passed through two electrolytic cells X and Y connected in series containing electrolytes and untill 2.8g of Fe deposited at the cathode of cell X. How long did the current flow? Calculate the mass Zn deposited at the cathode of cell Y.

(molar mass : Fe = 56 g mol^-1, Zn = 65.3 g mol^-1, 1F = 96500C mol^-1)

(b) In the plot of molar conductivity vs square root concentration , following curves are obtained for two electrolytes A and B:

Answer the following:

(i) Predict the nature of electrolyte A and B.

(ii) What happens on extrapolation of to concentration approaching zero for electrolytes A and B?

Question 28)

(a) How do you convert the following:

(i) Phenol to anisole

(ii)Ethanol to Propan-2-ol

(b)write the mechanism of the following reacion:

(c)Why phenol undergoes electrophilic substitution reaction more easly than benzene?

Question 29)

(a) Account for the following:

(i) o-nitophenol is more steam volatile than p-nitrophenol.

(ii) t-butyl chloride on heating eith sodium methoxide gives 2-methylpropene instead of t-butylmethylether.

(b) Write the reaction involved in the following:

(i) Reimer - Tiemann Reaction

(ii) Friedal - Crafts Alkylation Of Phenol

(c) Give simple test to distinguish between Ethanol and Phenol.

Question 30)

(a) Given reasons for the following:

(i) Sulphur in vapour state shows paramagnetic behaviour.

(ii) N-N bond is weaker than P-P bond.

(iii) Ozone iss thermodynamically less stable than oxygen.

(b) Write the names of gas relased when CU is added to

(i) dilute HNO₃ and

(ii) conc. HNO₃

Question 31)

When MnO₂ is fused with KOH in the presence of KNO₃ as an oxidizing agent, it gives a dark green compound (A). Compound (A) disproportionates in an acidic solution to give a purple compound (B). An alkaline solution of compound (B) oxidizes KI to compound (C) whereas an acidified solution of compound (B) oxidizes KI to (D). Identify (A), (B), (C), and (D).

Question 32)

Write the IUPAC name of the complex . Draw structures of geometrical isomers for this complex.

Question 33)

Using IUPAC norms write the formulae for the following :

1. Hexaamminecobalt(III) sulphate
2. Potassium trioxalatochromate(III)

Question 34)

Out of and , which one complex is

1. paramagnetic
2. more stable
3. inner orbital complex and
4. high spin complex

(Atomic no. of Co = 27)

Question 35)

(a) (i) Write the disproportionation reaction of .

(ii) Draw the structure of

(b) Account for the following:

(i) Although Fluorine has less negative electtron gain enthalpy yet F₂ is styrong oxidizing agent.

(ii) Acidic character decreases from N₂O₃ to Bi₂O₃ in group 15.

(c) Write a chemical reaction to test sulphur dioxide gas. Write chemical eqaution involved.

Question 36)

Write structures of compounds A and B in each of the following reactions :

Question 37)

The decomposition of NH 3 on a platinum surface is zero order reaction. If rate constant (k) is , how long will it take to reduce the initial concentration of NH 3 from 0.1 M to 0.064 M.

Question 38)

A 4% solution (w/w) of sucrose (M = 342 g mol^-1) in water has freezing point of 271.15K. Calculate the freezing point of 5% glucose (M = ) in water.

(Given: Frezzing point of water = 273.15K)

Question 1)

Why conductivity of silicon increases on doping with phosphorus ?

Question 2)

Write IUPAC name of the given compound :

Question 3)

Write two differences between an ideal solution and a non-ideal solution.

Question 4)

Write IUPAC name of the complex . Draw structures of geometrical isomers for this complex.

Question 5)

Using IUPAC norms write the formulae for the following :

(i) Pentaamminenitrito-O-cobalt chloride

(ii) Potassium tetracyanidonickelate

Question 6)

(i) Write the role of 'CO' in the purification of nickel.

(ii) What is the role of silica in the extraction of copper ?

(iii) What type of metals are generally extracted by electrolytic method ?

Question 7)

Give reasons for the following :

(i) Transition metals form alloys.

(ii) is basic whereas is acidic.

(iii) is a strong reducing agent.

Question 8)

(i) Why bithional is added in soap ?

(ii) Why magnesium hydroxide is a better antacid than sodium bicarbonate ?

(iii) Why soaps are biodegradable whereas detergents are non-biodegradable ?

Question 9)

Define the following terms with a suitable example in each :

(i) Antibiotics

(ii) Artificial sweeteners

(iii) Analgesics

Question 10)

Write the structures of main products when benzene diazonium chloride reacts with the following reagents :

(i)

(ii)

(iii)

Question 1)

What type of stoichiometric defect is shown by ZnS and why?

Question 2)

Write one stereochemical difference between and reactions.

Question 3)

State Henry's law and write its two application

Question 4)

Write the hybridization and magnetic character of the following complexes:

(i)

(ii)

(Atomic number of Fe = 26)

Question 5)

Write the structures of main componds A and B in each of the following reactions:

(i)

(ii)

Question 6)

How will you convert the following:

(i) Impure Nickel to pure Nickel

(ii) Zinc blende to Zinc metal

(iii) to Ag

Question 7)

Given reasons for the following:

(i) The transition metals generally form coloured compounds.

(ii) value for is highly positive than that for couple.

(iii) The chemistry of actinoids elements is not so smooth as that of the lanthanoids.

Question 8)

Write equations to the following reactions:

(i) Acetylation of aniline

(ii) Coupling reaction

(iii) Carbyl amine reaction

Question 9)

Define the following with a suitable examole in each:

(i) Oligosaccharides

(ii) Denaturation of protein

(iii) Vitamins

Question 10)

Write the reaction involved when D-glucose is treated with the following reagents:

(i) water

(ii)

(iii)

Question 1)

Out of and , which one shows Schottky defect and why?

OR

Why does apear yellow on heating?

Question 2)

Arrange the following in decreasing order of basic character :

Question 3)

What type of colloid is formed when a solid is dispersed in a liquid? Give an example.

Question 4)

Out of Chlorobenzene and Cyclohexyl chloride, which one is more reactive towards nucleophilic substitution reaction and why?

Question 5)

What is the basic structural difference between starch and cellulose?

OR

Write the products obtained after hydrolysis of DNA.

Question 6)

Write balanced chemical equations for the following processes :

(a) is passed throug slaked lime.

(b) gas is passed through an aqueous solution of salt.

Question 7)

Give reasons :

(a) Cooking is faster in pressure cooker than in cooking pan.

(b) Red Blood Cells (RBC) shrink when placed in saline water but swell in distilled water.

Question 8)

Define order of reaction. Predict the order of reaction in the given grahs :

(a)

(b)

where is the initial concentration of reactant and is half-life.

Question 9)

(a) Write two poisonous gases prepared from chlorine gas.

(b) Why does solution give blue colour on reaction with ammonia ?

Question 10)

When is fused with in the presence of air it gives a yellow solution of compound(A). Compound (A) on acidification gives comound (B). Compound (B) on reaction with forms an orange coloured compound (C). An acidified solution of comound (C) oxidises to (D). Identify (A), (B), (C) and (D).

Question 11)

Write IUPAC name of the complex . What type of structural isomerism is shownby this complex?

Question 12)

Using IUPAC norms, write the formulae for the following complexes:

(a) Hexaaquachromium(III)chloride

(b) Sodium trioxalatoferrate(III)

Question 13)

(a) Although both have hybridisation yet is paramagnetic and is diamagnetic. Give reason. (Atomic no. of Ni = 28)

(b) Write the electronic configuration of on the basis of crystal field theory when

(i)

(ii)

Question 14)

Write structures of main compounds A and B in each of the following reactions:

Question 15)

The following data were obtained for the reaction :

Experiment	[A]/M	[B]/M	Initial rate of formation of C/M min-1

(a) Find the order of reaction with respect to A and B.

(b) Write the rate law and overall order of reaction.

(c) Calculate the rate constant (k).

Question 16)

(a) Write the dispersed phase and dispersion medium of dust.

(b) Why is physisortion reversible whereas chemisorption is irreversible?

(c) A colloidal sol is prepared by the method given in the figure. What is the charge on AgI colloidal particles in the test tube? How is this sol represented?

Question 17)

An element X with an atomic mass of has density . If the volume of unit cell is , identify the type of cubic unit cell.

Question 18)

A solution containing is isotonic with a solution containing . Calculate the degree of dissociation of KCl solution. Assume that both the solutions have same temperature.

Question 19)

Write the name and principle of the method used for refining of (a) Zinc, (b) Germanium, (c) Titanium.

Question 20)

Give reasons for the following :

(a) Transition metals form complex compounds.

(b) values for are more negative than expected.

(c) Actinoids show wide range of oxidation states.

Question 21)

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

(a) Nylon-6

(b) Terylene

(c) Buna-N

Question 22)

(a) Is a homopolymer or copolymer? Give reason.

(b) Write the monomers of the following polymer:

(c) Write the role of benzoyl peroxide in polymerisation of ethene.

Question 23)

(a) Pick out the odd one from the following on the basis of their medicinal properties:

Equanil, Seconal , Bithional, Luminal

(b) What type of detergents are used in dishwashing liquids?

(c) Why is the use of aspartame limited to cold foods?

Question 24)

Define the following terms with a suitable example of each:

(a) Antibiotics

(b) Antiseptics

(c) Anionic detergents.

Question 25)

Among all the isomers of molecular formula identify

(a) the one isomer which is optically active.

(b) the one isomer which is highly reactive towards

(c) the two isomers which give same product on dehydrohalogenation with alcoholic .

Question 26)

Complete the following reactions :

(a)

(b)

(c)

Question 27)

How do you convert the following :

(a) N-phenylethanamide to p-bromoaniline

(b) Benzene diazonium chloride to nitrobenzene

(c) Benzoic acid to aniline

Question 28)

(a) Give reasons :

(i) Benzoic zcid is a stronger acid than acetic acid.

(ii) Methanal is more reactive towards nucleophilic addition reaction than ethanal.

(b) Give a simple chemical test to distinguish between propanal and propanone.

Question 29)

(a) What are the products of hydrolysis of maltose?

(b) What type of bonding provides stability to structure of protein?

(c) Name the vitamin whose deficiency causes pernicious anaemia.

Question 30)

Define the following terms :

(a) Invert sugar

(b) Native protein

(c) Nucleotide

Question 31)

(a) The conductivity of acetic acid is . Calculate the dissociation constant if for acetic acid is .

(b) Write Nernst equation for the reaction at :

(c) What are secondary batteries? Give an example.

Question 32)

(a) Represent the cell in which the following reaction takes place :

Calculate its emf if .

(b) How does molar conductivity vary with increase in concentration for strong electrolyte and weak electrolyte? How can you obtain limiting molar conductivity for weak electrolyte?

Question 33)

(a) Give equations of the following reactions:

(i) Phenol is treated with

(ii) Propene is treated with followed by

(iii) Sodium t-butoxide is treated with

(b) How will you distinguish between and ?

(c) Arrange the following in increasing order of acidity :

Phenol, ethanol, water

Question 34)

(a) How can you obtain Phenol from (i) Cumene, (ii) Benzene sulphonic acid, (iii) Benzene diazonium chloride?

(b) Write the structure of the major product obtained from dinitration of

(c) Write the reaction involved in Kolbe's reaction.

Question 35)

(a) Give one example to show the anomalous reaction of fluorine.

(b) What is the structural difference between white phosphorus and red phosphorus?

(c) What happens when reacts with

(d) Why is a better reducing agent than ?

(e) Arrange the following acids in the increasing order of their acidic character :

and

Question 36)

(a) Account for the following :

(i) Tendency to show oxidation state decreases from to in group .

(ii) Acidic character increases from to

(iii) is more reactive than whereas is more reactive than

(b) Draw the structure of (i) .

Question 1)

Arrange the following in increasing order of pKb values :

Question 2)

What type of colloid is formed when a liquid is dispersed in a solid ? Give an example.

Question 3)

Give reasons :

1. A decrease in temperature is observed on mixing ethanol and acetone.
2. Potassium chloride solution freezes at a lower temperature than water.

Question 4)

Define the following terms with a suitable example of each :
(a) Chelate complex
(b) Ambidentate ligand

Question 5)

Using IUPAC norms, write the formulae for the following complexes :
(a) Tetraamminediaquacobalt(III) chloride
(b) Dibromidobis(ethane-1,2-diamine)platinum(IV) nitrate

Question 6)

(a) Using valence bond theory, write the hybridisation and magnetic character of the complex. Atomic Number of Fe = 26)

(b) Write the electronic configuration of d 6 on the basis of crystal field theory when

1. and
2. 

Question 7)

(a) Write the dispersed phase and dispersion medium of milk.
(b) Why is adsorption exothermic in nature?
(c) Write Freundlich adsorption isotherm for gases at high pressure.

Question 8)

Write the name and principle of the method used for refining of (a) Tin, (b) Copper, (c) Nickel.

Question 9)

Give reasons for the following :

(a) Transition metals show variable oxidation states.
(b) E^o value for (Zn²⁺/Zn) is negative while that of (Cu²⁺/Cu) is positive.
(c) Higher oxidation state of Mn with fluorine is +4 whereas with oxygen is +7.

Question 10)

(a) Write one example each of

(i) Thermoplastic polymer
(ii) Elastomers

(b) Arrange the following polymers in the increasing order of their intermolecular forces :
Polythene, Nylon-6,6, Buna-S

(c) Which factor provides crystalline nature to a polymer like Nylon?

Question 11)

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

(a) Nylon-6,6
(b) Bakelite
(c) Buna-S

Question 1)

Arrange the following in decreasing order of solubility in water :

Question 2)

What type of colloid is formed when a solid is dispersed in a gas? Give an example.

Question 3)

What is the difference between amylose and amylopectin ?

Question 4)

Give reasons :

(a) An increase in temperature is observed on mixing chloroform and acetone.

(b) Aquatic animals are more comfortable in cold water than in warm water.

Question 5)

Define the following terms with a suitable example of each:

(a) Polydentate ligand

(b) Homoleptic complex

Question 6)

Write structures of main compounds A and B in each of the following reactions :

(a)

(b)

Question 7)

(a) Write the dispersed phase and dispersion medium of butter.

(b) Why does physisorption decrease with increase in temperature ?

(c) A colloidal sol is prepared by the method given in the figure. What is the charge on Agl colloidal particles formed in the test tube?How is this sol represented ?

Question 8)

Write the principle of the following :

(a) Hydraulic washing

(b) Chromatography

(c) Froth-floatation process

Question 9)

Give reasons for the following :

(a) Transition metals have high enthalpies of atomization.

(b) Manganese has lower melting point even though it has a higher number of unpaired electrons for bonding.

(c) is a strong oxidising agent.

Question 10)

Write the structure of monomers used for getting the following polymers:

(a) Novolac

(b) Neoprene

(c) Buna-S

Question 11)

(a) Write the product when D-glucose reacts with .

(b)What type of bonding provides stability to structure of protein.

(c) Name the vitamin whose deficiency causes pernicious anaemia.

Question 12)

(a) Write one example each of

(i) Cross-linked polymer

(ii) Natural polymer

(b) Arrange the following in the increasing order of their intermolecular forces:

Terylene, Buna-N, Polystyrene

(c) Define biodegradable polymers with an example.

Question 13)

Define the following terms:

(a) Invert sugar

(b) Native protein

(c) Nucleotide

Question 14)

Using IUPAC norms, write the formulae for the following complexes :

(a) Potassium tri(oxalato) chromate(III)

(b) Hexaaquamanganese (II) sulphate

Question 1)

Write the IUPAC name of the following compound :

Question 2)

Arrange the following in increasing order of their acidic character :

Benzoic acid, Phenol, Cresol

Question 3)

Write IUPAC name of the complex

Question 4)

Using IUPAC norms, write the formula of Ammonium tetrafluoridocobaltate (II).

Question 5)

What is the difference between a glycosidic linkage and a peptide linkage ?

Question 6)

What is the difference between Nucleotide and Nucleoside ?

Question 7)

What happens when is doped with ? What is the name of this defect ?

Question 8)

What type of defect is shown by in

(a) stoichiometric defects, and

(b) non-stoichiometric defects ?

Question 9)

(a) Out of molal aqueous solution of glucose and molal aqueous solution of , which one will have higher boiling point and why ?

(b) Predict whether van’t Hoff factor, is less than one or greater than one in the following :

(i) dissolved in water

(ii) dissolved in benzene

Question 10)

Complete and balance the following equations :

(a)

(b)

Question 11)

Write balanced chemical equations involved in the following reactions :

(a) Fluorine gas reacts with water.

(b) Phosphine gas is absorbed in copper sulphate solution.

Question 12)

Draw structures of the following :

(a)

(b)

Question 13)

Write anode and cathode reactions that occur in dry cell. How does a dry cell differ from a mercury cell ?

Question 14)

Account for the following :

(a) Gabriel phthalimide synthesis is not preferred for preparing aromatic primary amines.

(b) On reaction with benzene sulphonyl chloride, primary amine yields product soluble in alkali whereas secondary amine yields product insoluble in alkali.

Question 15)

Write structures of compounds A and B in each of the following reactions :

Question 16)

(a) Following reaction takes place in the cell :

Calculate of the reaction .

[Given :

(b) How can you determine limiting molar conductivity, for strong electrolyte and weak electrolyte ?

Question 17)

Define the following with a suitable example, of each :

(a) Coagulation

(b) Multimolecular colloid

(c) Gel

Question 18)

(a) Out of starch and ferric hydroxide sol, which one can easily be coagulated and why?

(b) What is observed when an emulsion is centrifuged?

(c) What is the role of promoters and poisons in catalysis?

Question 19)

(a) An element crystallizes in bcc lattice with a cell edge of . The density of the element is . Calculate the molar mass of the element.

(b) What type of semiconductor is obtained when

(i) is doped with In?

(ii) is doped with P?

Question 20)

A solution 0·1 M of is dissolved to the extent of . What would be its osmotic pressure at ?

Question 21)

Write down the reactions taking place in blast furnace related to the metallurgy of iron in the temperature range 500 K – 800 K. What is the role of limestone in the metallurgy of iron ?

Question 22)

What happens when

(a) Silver is leached with in the presence of air?

(b) Copper matte is charged into silica lined converter and hot air blast is blown?

(c) is added in an ore containing PbS and ZnS during concentration by froth floatation method?

Question 23)

Give reasons for the following :

(a) Dioxygen is a gas but sulphur a solid.

(b) NO (g) released by jet airplanes is slowly depleting the ozone layer.

(c) Interhalogens are more reactive than pure halogens

Question 24)

Write the structures of monomers used to obtain the following polymers :

(a) Neoprene

(b) PHBV

(c) Bakelite

Question 25)

(a) Arrange the following polymers in decreasing order of their intermolecular forces: Bakelite, Polythene, Buna-S, Nylon-6,6

(b) Write the monomers of the following polymer :

(c) What is the structural difference between high-density polythene (HDP) and low-density polythene (LDP)?

Question 26)

(a) Why are metal hydroxides better alternatives than sodium hydrogen carbonate in antacids?

(b) Why is aspirin used in the prevention of heart-attacks?

(c) Why antihistamines do not affect the secretion of acid in the stomach ?

Question 27)

Define the following terms with a suitable example of each :

(a) Tranquilizers

(b) Antibiotics

(c) Non-ionic detergents

Question 28)

(a) Out of which one is more reactive towards SN2 reaction and why?

(b) Out of which one is more reactive towards nucleophilic substitution reaction and why?

(c) Out of which one is optically active and why?

Question 29)

What happens when

(a) Salicylic acid is treated with ?

(b) Phenol is oxidized with ?

(c) Anisole is treated with/anhydrous ?

Write the chemical equation in support of your answer.

Question 30)

(a) Give one chemical test as an evidence to show that

and are ionization isomers.

(b) is paramagnetic while is diamagnetic though both are tetrahedral. Why ? (Atomic no. of)

(c) Write the electronic configuration of on the basis of crystal field theory when it forms an octahedral complex in the presence of

(i) strong field ligand, and

(ii) weak field ligand. (Atomic no. of )

Question 31)

Define the following terms with a suitable example of each :

(a) Anomers

(b) Essential amino acids

(c) Denaturation of protein

Question 32)

(a) Define order of reaction. How does order of a reaction differ from molecularity for a complex reaction?

(b) A first-order reaction is complete in 25 minutes. Calculate the time for completion of the reaction.

Question 33)

(a) The decomposition of a hydrocarbon has value of rate constant as at . At what temperature would rate constant be if energy of activation is

(b) Write a condition under which a bimolecular reaction is kinetically first order. Give an example of such a reaction.

Question 34)

(a) Predict the main product of the following reactions :

(b) Give a simple chemical test to distinguish between

(c) Why is alpha hydrogen of carbonyl compounds acidic in nature?

Question 35)

(a) Write the main product formed when propanal reacts with the following reagents :

(i) 2 moles of in presence of dry

(ii) Dilute

(iii) followed by heating with in ethylene glycol

(b) Arrange the following compounds in increasing order of their property as indicated :

(i) — acid character

(ii) Acetone, Acetaldehyde, Benzaldehyde, Acetophenone — reactivity towards the addition of .

Question 36)

(a) Account for the following :

(i) Manganese shows maximum number of oxidation states in 3d series.

(ii) value for couple is much more positive than that for

.

(iii) is colourless whereas is coloured in an aqueous solution.

(b) Write the chemical equations for the preparation of from . Why does purple colour of acidified permanganate solution decolourise when it oxidises to ?

Question 37)

(a) Write one difference between transition elements and p-block elements with reference to variability of oxidation states.

(b) Why do transition metals exhibit higher enthalpies of atomization?

(c) Name an element of lanthanoid series which is well known to shown oxidation state. Is it a strong oxidising agent or reducing agent ?

(d) What is lanthanoid contraction? Write its one consequence.

(e) Write the ionic equation showing the oxidation of salt by acidified dichromate solution.

Question 1)

Using IUPAC norms write the formula of Hexaamminecobalt(III) sulphate.

Question 2)

Why is more easily hydrolysed than ?

Question 3)

Write the IUPAC name of the following compound:

Question 4)

Arrange the following in increasing order of their boiling point:

Question 5)

Complete and balance the following equations:

(a)

(b)

Question 6)

Write balanced chemical equations involved in the following reactions:

(a) Chlorine gas reacts with cold and dilute NaOH.

(b) Calcium phosphide is dissolved in water.

Question 7)

Draw structures of the following:

a)

b)

Question 8)

(a) Write the reaction that occurs at anode on electrolysis of concentrated using platinum electrodes.

(b) What is the effect of temperature on ionic conductance?

Question 9)

Write structures of compounds A and B in each of the following reactions:

Question 10)

Write the structures of monomers used to obtain the following polymers:

(a) Buna-S

(b) Glyptal

(c) Nylon-6

Question 11)

(a) Arrange the following polymers in increasing order of their intermolecular forces:

Polyvinylchloride, Neoprene, Terylene

(b) Write one example each of

(i) Natural Polymer

(ii) Thermosetting polymer

(c) What is the significance of numbers 6,6 in the polymer Nylon-6,6?

Question 12)

(a) Which one of the following is disinfectant?

0.2% solution of phenol or 1% solution of phenol.

(b) What is the difference between agonists and antagonists?

(c) Write one example each of

(i) Artificial sweetener

(ii) Antacids

Question 13)

Define the following terms with a suitable example of each:

(a) Antiseptics

(b) Bactericidal antibiotics

(c) Cationic detergents

Question 1)

Write the IUPAC name of the following compound:

Question 2)

Write IUPAC name of the complex

Question 3)

Arrange the following in increasing order of their acidic character:

Ethanol, Phenol, Water

Question 4)

a)

b)

Question 5)

Write balanced chemical equations involved in the following reactions :

1. reacts with .
2. is heated with .

Question 6)

Write any two oxoacids of sulphur and draw their structures.

Question 7)

Write the name of two fuels other than hydrogen used in fuel cell. Write two advantages of fuel cell over an ordinary cell.

Question 8)

Give reasons for the following :

1. Acidic character decreases from to
2. All the P – Cl bonds in are not equivalent.
3. HF is a weaker acid than HCl in an aqueous solution.

Question 9)

Write the structures of monomers used to obtain the following polymers :

1. Natural rubber
2. PVC
3. Nylon-6,6

Question 10)

Write the mechanism of free radical polymerisation of ethene.

Question 11)

Question 12)

Define the following terms with a suitable example of each :

1. Tertiary structure of protein
2. Essential amino acids
3. Disaccharides

Question 1)

Name the defect in the following crystal :

Question 2)

When a coordination compound is mixed with , two moles of are precipitated per mole of the compound. What is the structural formula of the coordination compound ?

Question 3)

What is the difference between a complex and a double salt ?

Question 4)

Define associated colloid with an example.

Question 5)

Why is t-butyl bromide more reactive towards reaction as compared to n-butyl bromide ?

Question 6)

Write the reaction involved in the Hoffmann bromamide degradation reaction.

Question 7)

Propanamine and N,N-dimethylmethanamine contain the same number of carbon atoms, even though Propanamine has higher boiling point than N,N-dimethylmethanamine. Why ?

Question 8)

Give reasons for the following :

(a) Aquatic species are more comfortable in cold water than warm water.

(b) At higher altitudes people suffer from anoxia resulting in inability to think.

Question 9)

What type of azeotropic mixture will be formed by a solution of acetone and chloroform ? Justify on the basis of strength of intermolecular interactions that develop in the solution.

Question 10)

Explain with a graph, the variation of molar conductivity of a strong electrolyte with dilution.