Question Set B

CBSE 12th Chemistry Chemical Kinetics Important Questions And Answers Study Material - QB365

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Questions:

Multiple Choice Question

48 x 1 = 48

Mark the correct order of decreasing acid strength of the following compounds.

(a)

V > IV > II > I > III

(b)

II > IV > I > III > V

(c)

IV > V > III > II > I

(d)

V > IV > III > II > I

The formula of the complex dichloridobis (ethane-1, 2-diamine) platinum (IV) nitrate is

(a)

[PtCl₂(en)₂(NO₃)₂]

(b)

[PtCl₂(en)₂] (NO₃)₂

(c)

[PtCl₂(en)₂(NO₃)] NO₃

(d)

[Pt(en)₂(NO₃)₂] Cl₂

Which reagent is required for one step conversion of benzene diazonium chloride to bromobenzene?

(a)

PBr₃

(b)

HBr

(c)

Cu₂Br₂

(d)

Br₂

Alkenes decolourise bromine water in presence of CCl₄ due to formation of

(a)

allyl bromide

(b)

vinyl bromide

(c)

bromoform

(d)

vicinal dibromide

Out of the following alkenes, the one which will produce tertiary butyl alcohol on acid catalysed hydration is

(a)

CH₃CH₂CH = CH₂

(b)

CH₃CH = CH₂

(c)

CH₃ - CH = CH - CH₃

(d)

(CH₃)₂C = CH₂

Deficiency of vitamin B, causes the disease

(a)

convulsions

(b)

beri beri

(c)

cheilosis

(d)

sterility

Diethyl amine, when treated with HNO₃ gives

(a)

Diethyl ammonium nitrite

(b)

Ethyl alcohol

(c)

N-nitroso diethyl amine

(d)

Triethyl ammonium nitrite

The product formed by the reaction of an aldehyde with a primary amine is

(a)

Carboxylic acid

(b)

Aromatic acid

(c)

Schiff's base

(d)

Ketone

(a)

(b)

(c)

(d)

10.

Salicylic acid on reaction with CH₃OH in presence of Cone. H₂SO₄gives

(a)

Methyl salicylate (Iodex)

(b)

Benzoic acid

(c)

Methyl benzoate

(d)

Phenol

11.

Identify 'C' in the following:

(a)

Water

(b)

Ethanol

(c)

Propanone

(d)

Cumene hydroperoxide

12.

3-methyl pent-2-ene on reaction with HBr in presence of peroxide forms an addition product. The number of possible stereoisomers for the product are

(a)

(b)

(c)

(d)

13.

In the first order reaction the concentration of reactant decreases from 0.6 M to 0.3 M in 30 minutes. The time taken for the concentration to change from 0.1 M to 0.025 M:

(a)

60 min

(b)

30 min

(c)

15 min

(d)

50 min

14.

Pyridoxin is also known as

(a)

vitamin B₂

(b)

vitamin B₆

(c)

vitamin B₁₂

(d)

vitamin B₁

15.

Benzene diazonium chloride when reacts with hypophosphorus acid produces

(a)

Benzene

(b)

Phenol

(c)

Phenol isocyanide

(d)

Phenyl phosphate

16.

After introducing the factor P, expression for the rate of a reaction, becomes

(a)

\(Rate =\frac{Z_{A B} e^{-E_{a} / R T}}{P}\)

(b)

\( Rate =P Z_{A B} e^{-E_{a}/RT}\)

(c)

\( Rate =\frac{Z_{A B}.P}{e^E_{a}/RT}\)

(d)

\(Rate=\frac{e^{E_{a} / R t}}{P Z_{AB}}\)

17.

The reaction,
2N₂O₅ \( \rightleftharpoons \) 2N₂O₄ +O₂ is

(a)

bimolecular and first order

(b)

unimolecular and second order

(c)

bimolecular and second order

(d)

unimolecular and first order

18.

In a reaction, 2x ⟶ y, the concentration of x decreases from 3.0 M to 1.5 Min 4 min. The rate of the reaction is

(a)

0.187 M min^-1

(b)

1.87 M min^-1

(c)

3.75 x 10^-1M min^-1

(d)

0.75 M min^-1

19.

The correct sequence of reactions to convert p-nitrophenol into quinol involves

(a)

reduction, diazotization and hydrolysis

(b)

hydrolysis, diazotization and reduction

(c)

hydrolysis, reduction and diazotization

(d)

diazotization, reduction and hydrolysis

20.

Which gives black precipitate on reaction with CS₂ followed by addition of HgCl₂?

(a)

(CH₃)₃CNH₂

(b)

(C₂H₅)₂NH

(c)

(CH₃)₃N

(d)

all the three

21.

The compound which gives an oily nitrosoamine on reaction with nitrous acid at low temperature is

(a)

CH₃NH₂

(b)

(CH₃)₂CHNH₂

(c)

CH₃-NH-CH₃

(d)

(CH₃)₃N

22.

Mendius reduction converts an alkyl cyanide to

(a)

a primary amine

(b)

an aldehyde

(c)

a ketone

(d)

an oxime

23.

Which of the following statements about benzaldehyde is are true ?

(a)

Reduces Tollens' reagent

(b)

Undergoes aldol condensation

(c)

Undergoes Cannizzaro reaction

(d)

Does not form an addition compound with sodium hydrogen sulphite

24.

Which one of the following ions is the most stable in aqueous solution ?

(a)

Mn²⁺

(b)

Cr³⁺

(c)

V³⁺

(d)

Ti³⁺

25.

P \(\xrightarrow [ 2.{ H }_{ 3 }{ O }^{ + } ]{ 1.C{ H }_{ 3 }MgBr } \) R\(\xrightarrow [2.\triangle ]{ 1.dil.NaOH } \) 4-methylpent-3-en-2-one P is

(a)

propanone

(b)

ethanamine

(c)

ethaneitrile

(d)

ethanal

26.

Identify the combination of compounds that undergo Aldol condensation followed by dehydration to produce but-2-enal.

(a)

methanal and ethanal

(b)

two moles of ethanal

(c)

methanal and propanone

(d)

two moles of ethanol

27.

Compound 'A' of molecular formula C₄H₁₀O on treatment with Lucas reagent at room temperature give compound B. When compound 'B' is heated with alcoholic KOH, it gives isobutene. Compound 'A' and 'B' are respectively

(a)

2-methyl-2-propanol and 2-chloro-2-methyl-propane

(b)

2-methyl-1-propanol and 1-chloro-2-methyl-propane

(c)

2-methyl-1-propanol and 2-chloro-2-methyl-propane

(d)

butan-2-ol and 2-chlorobutane

(e)

butan-1-ol and 1-chlorobutane

28.

Acid catalysed hydration of alkene is an example for

(a)

free radical substitution

(b)

nucleophilic substitution

(c)

nucleophilic addition

(d)

electrophilic addition

(e)

electrophilic substitution

29.

KMnO₄ acts as an oxidising agent in alkaline medium. When alkaline KMnO₄ is treated with KI, iodide ion is oxidised to ............ .

(a)

I₂

(b)

IO^-

(c)

\({ IO }_{ 3 }^{ - }\)

(d)

\({ IO }_{ 4 }^{ - }\)

30.

On addition of small amount of KMnO₄ to concentrated H₂SO₄, a green oily compound is obtained which is highly explosive in nature, Identify the compound from the following.

(a)

Mn₂O₇

(b)

MnO₂

(c)

MnSO₄

(d)

Mn₂O₃

31.

A device that converts energy of combustion of fuels like hydrogen and methane directly into electrical energy is known as

(a)

dynamo

(b)

Ni-Cd cell

(c)

fuel cell

(d)

electrolytic cell

32.

Among the following complexes (K-P) K₃[Fe(CN)₆] (K), [Co(NH₃)₆]Cl₃ (L), Na₃[Co(oxalate)₃](M), [Ni(H₂O)₆]Cl₂ (N), K₂[Pt(CN)₄] (O) and [Zn(H₂O)₆] (NO₃)₂ (P) the diamagnetic complexes are

(a)

K, L, M, N

(b)

K, M, O, P

(c)

L, M, O, P

(d)

L, M, N, O

33.

When 0.01 mole of a cobalt complex is treated with excess silver nitrate solution, 4.305 g silver chloride is precipitated. The formula of the complex is

(a)

[Co(NH₃)₃Cl₃]

(b)

[Co(NH₃)₅Cl]Cl₂

(c)

[Co(NH₃)₆]Cl₃

(d)

[Co(NH₃)₄Cl₂]NO₃

(e)

[Co(NH₃)₄Cl₂]Cl

34.

Electrolysis of dilute aqueous NaCl solution was carried out by passing 10 milli ampere current. The time required to liberate 0.01 mol of H₂ gas at the cathode is (1 Faraday = 96500 C mol^-1)

(a)

9.65 x 10⁴ sec

(b)

19.3 x 10⁴ sec

(c)

28.95 x 10⁴ sec

(d)

38.6 x 10⁴ sec

35.

The dark blue colour of the solution formed when excess of ammonia is added to a solution of copper (II) sulphate is due to the presence of the ion

(a)

[Cu(OH)₄ (H₂O)₂]^2-

(b)

[Cu(H₂O)₆]²⁺

(c)

[Cu(NH₃)₂ (H₂O)₄]²⁺

(d)

[Cu(NH₃)₄ (H₂O)₂]²⁺

36.

Which of the following is an outer orbital complex?

(a)

[Fe(CN)₆]⁴^-

(b)

[FeF₆]^3-

(c)

[Co(NH₃)₆]³⁺

(d)

[Co(CN)₆]²⁺

37.

The primary and secondary valencies of chromium in the complex ion, dichlorodioxalatochromium (III) are respectively

(a)

3,4

(b)

4,3

(c)

3,6

(d)

6,3

38.

Name a member of lanthanide series which is well known to exhibit + 4 oxidation state :

(a)

(b)

(c)

(d)

39.

Which of the following oxides of chromium is amphoteric in nature ?

(a)

CrO

(b)

Ct₂O₃

(c)

CrO₃

(d)

CrO₅

40.

For the given cell, \(Mg|{ Mg }^{ 2+ }||{ Cu }^{ 2+ }|Cu\)

(a)

Mg is cathode

(b)

Cu is cathode

(c)

The cell reaction is \(Mg+{ Cu }^{ 2+ }\longrightarrow { Mg }^{ 2+ }+Cu\)

(d)

Cu is the oxidising agent

41.

\({ E }_{ cell }^{ \circleddash }=1.1V\) for Daniell cell. Which of the following expressions are correct description of state of equilibrium in this cell?

(a)

1.1 = K_c

(b)

\(\frac { 2.303RT }{ 2F } \log { { K }_{ c } } =1.1\)

(c)

\(\log { { K }_{ c } } =\frac { 2.2 }{ 0.059 } \)

(d)

\(\log { { K }_{ c } } =1.1\)

42.

Which of the following statement is not correct about an inert electrode in a cell ?

(a)

It does not participate in the cell reaction

(b)

It provides surface either for oxidation or for reduction reaction

(c)

It provides surface for conduction of electrons

(d)

It provides surface for redox reaction

43.

Which one of the following statement is always true about the spontaneous cell reaction in a galvanic cell?

(a)

\({ E_{ cell } }^{ ° }>0,{ \Delta G }^{ ° }>0,Q>{ K }_{ c }\)

(b)

\({ E_{ cell } }^{ ° }<0,{ \Delta G }^{ ° }<0,Q<{ K }_{ c }\)

(c)

\({ E_{ cell } }^{ ° }>0,{ \Delta G }^{ ° }<0,Q<{ K }_{ c }\)

(d)

\({ E_{ cell } }^{ ° }>0,{ \Delta G }^{ ° }<0,Q>{ K }_{ c }\)

44.

Low concentration of oxygen in the blood and tissues of people living at high altitude is due to _____________.

(a)

low temperature

(b)

low atmospheric pressure

(c)

high atmospheric pressure

(d)

both low temperature and high atmospheric pressure

45.

If sodium sulphate is considered to be completely dissociated into cations and anions in aqueous solution, the change in freezing point of water \((\Delta { T }_{ f })\), when 0.01 mol of sodium sulphate is dissolved in 1 kg of water, is (K_f = 1.86 K kg mol^-1).

(a)

0.0744K

(b)

0.0186K

(c)

0.0372K

(d)

0.0558K

46.

The osmotic pressure of 0.1 M aqueous solution of NaCl is ................ Osmotic pressure of 0.1 M aqueous solution of glucose

(a)

equal to

(b)

less than

(c)

half of

(d)

nearly double

47.

The system that forms maximum boiling azeotrope is

(a)

carbon disulphide-acetone

(b)

benzene-tolune

(c)

acetone-chloroform

(d)

n-hexane-n-heptane

48.

5ml of 1 N HCI, 20ml of N/2 H₂SO₄ and 30ml of N/3 HNO₃ are mixed together and the volume made to one litre. The normality of the resulting solution is

(a)

N/5

(b)

N/10

(c)

N/20

(d)

N/40

Assertion and reason

2 x 1 = 2

49.

Assertion : Copper sulphate can be stored in zinc vessel.
Reason : Zinc is less reactive than copper.
Codes :
(a) Assertion and reason both are correct statements and reason is correct explanation for assertion.
(b) Assertion and reason both are correct statements but reason is not correct explanation for assertion.
(c) Assertion is correct statement but reason is wrong statement.
(d) Assertion is wrong statement but reason is correct statement.

50.

In the following questions. an Assertion (A) is followed by a corresponding Reason (R) Use the following keys to choose the appropriate answer.
Assertion (A) The ligands of nitro and nitrito are called ambidentate ligands .
Reason (R) These ligands give linkage isomers.
Codes:
(a) Both (A) and (R) are correct, (R) is the correct explanation of (A).
(b) Both (A) and (R) are correct, (R) is not the correct explanation of (A).
(c) (A) is correct; (R) is incorrect.
(d) (A) is incorrect; (R) is correct.

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Answers Key:

Multiple Choice Question

48 x 1 = 48

(b)
II > IV > I > III > V

(a)
[PtCl₂(en)₂(NO₃)₂]

(d)
vicinal dibromide

(d)
(CH₃)₂C = CH₂

(b)
beri beri

10.

(a)
Methyl salicylate (Iodex)

11.

12.

(d)
4

13.

(a)
60 min

14.

(b)
vitamin B₆

15.

(a)
Benzene

16.

(b)
\( Rate =P Z_{A B} e^{-E_{a}/RT}\)

17.

(a)
bimolecular and first order

18.

(a)
0.187 M min^-1

19.

(a)
reduction, diazotization and hydrolysis

20.

Only \({ 1 }^{ \circ }\) amines undergo Hofmann Mustard oil reaction and thus give a black ppt. of HgS.

21.

\({ 2 }^{ \circ }\) Amines, i.e., (CH₃)₂NH, on treatment with HNO₂ give oily nitrosamines.

22.

(a)
a primary amine

23.

24.

(b)
Cr³⁺

25.

26.

(b)
two moles of ethanal

27.

(a)
2-methyl-2-propanol and 2-chloro-2-methyl-propane

28.

electrophilic addition

29.

30.

(a)
Mn₂O₇

31.

32.

33.

34.

(b)
19.3 x 10⁴ sec

35.

(d)
[Cu(NH₃)₄ (H₂O)₂]²⁺

36.

(b)
[FeF₆]^3-

37.

38.

(a)
Ce

39.

(b)
Ct₂O₃

40.

(b)
Cu is cathode

41.

(b)
\(\frac { 2.303RT }{ 2F } \log { { K }_{ c } } =1.1\)

42.

(d)
It provides surface for redox reaction

43.

44.

Body temperature of the human body remains constant. Low concentration of oxygen in the blood at altitude is due to low atmospheric pressure.

45.

(d)
0.0558K

46.

(d)
nearly double

47.

Acetone-chloroform mixture shows negative deviation from Raoult's law. Hence, for a particular composition, it has lowest vapour pressure and maximum boiling point.

48.

\({ N }_{ 1 }{ V }_{ 1 }+{ N }_{ 2 }{ V }_{ 2 }+{ N }_{ 3 }{ V }_{ 3 }={ N }_{ 4 }{ V }_{ 4 }={ N }_{ 4 }({ V }_{ 1 }+{ V }_{ 2 }+{ V }_{ 3 })\)

Assertion and reason

2 x 1 = 2

49.

(d) Assertion is wrong statement but reason is correct statement.

50.

(a) When a monodentate ligand has two possible donor atoms and attached in two ways to the central metal atom then that ligand is called ambidentate ligand. e.g. nitro (NO₂) and nitrito (ONO). These show linkage isomerism. Both (A) and (R) are correct and (R) is the correct explanation of (A).