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Questions:

Multiple Choice Question

50 x 1 = 50

Which is the monomer of neoprene in the following?

(a)

(b)

\(\mathrm{CH}_{2}=\mathrm{CH}-\mathrm{C} \equiv \mathrm{CH}\)

(c)

\(\mathrm{CH}_{2}=\mathrm{CH}-\mathrm{CH}=\mathrm{CH}_{2}\)

(d)

Identify, the geometrical isomer of platinum complex with the ligands NH₃& Cl

Choose the correct option

(a)

i & ii

(b)

ii & iii

(c)

i & iii

(d)

ii & iv

The C₆₀ molecule is called as_________ because of its structure.

(a)

buck minster fullerene

(b)

bucky balls

(c)

diamond

(d)

both (a) & (b)

Using the data given below find out the strongest reducing agent ______.
\({ E }_{ { Cr }_{ 2 }{ O }_{ 7 }^{ 2- } }^{ o }{ Cr }^{ 3+ }=1.33V{ ,E }_{ { Cl }_{ 2 }{ / }{ Cl }^{ - } }^{ o }=1.36V\)
\({ E }_{ { Mn }O_{ 4 }^{ - } }^{ 0 }/{ Mn }^{ 2+ }=1.51V,{ E }_{ { Cr }^{ 3+ }/Cr }^{ o }=-0.74V\)

(a)

(b)

Cr³⁺

(c)

Cl^-

(d)

Mn²⁺

The relationship between degree of dissociation of a weak acid and its dissociation constant in a very dilute solution is _______.

(a)

K_a = α²C

(b)

K_a = \(\frac{α^2C}{(1+α)}\)

(c)

K_a = \(\frac{α^2}{(1+α)C}\)

(d)

K_a = \(\frac{α}{C(1+α)}\)

Which one of the following structures represents nylon 6,6 polymer?

(a)

(b)

(c)

(d)

The correct statement regarding RNA and DNA respectively is ______.

(a)

the sugar component in RNA is an arabinos and the sugar component in DNA is ribose

(b)

the sugar component in RNA is 2’-deoxyribose and the sugar component in DNA is arabinose

(c)

the sugar component in RNA is an arabinose and the sugar component in DNA is 2’-deoxyribose

(d)

the sugar component in RNA is ribose and the sugar component in DNA is 2’-deoxyribose

Identify X in the sequence give below

(a)

(b)

(c)

(d)

_______.

(a)

H₃PO₂ and H₂O

(b)

H⁺/H₂O

(c)

HgSO₄/H₂SO₄

(d)

Cu₂Cl₂

10.

CH₃CH₂ Br \(\overset { aqNaOH }{ \underset { \Delta }{ \longrightarrow } } A\overset { { KMnO }_{ 4 }{ /H }^{ + } }{ \underset { \Delta }{ \longrightarrow } } B\overset { { NH }_{ 3 } }{ \underset { \Delta }{ \longrightarrow } } C\overset { { Br }_{ 2 }/NaOH }{ \longrightarrow } D\) D' is________.

(a)

bromomethane

(b)

α - bromo sodium acetate

(c)

methanamine

(d)

acetamide

11.

In which of the following reactions new carbon – carbon bond is not formed?

(a)

Aldol condensation

(b)

Friedel craft reaction

(c)

Kolbe’s reaction

(d)

Wolf kishner reduction

12.

The IUPAC name of

(a)

but – 3- enoicacid

(b)

but – 1- ene-4-oic acid

(c)

but – 2- ene-1-oic acid

(d)

but -3-ene-1-oicacid

13.

Predict the product Z in the following series of reactions Ethanoic acid \(\overset { { PCI }_{ 5 } }{ \longrightarrow } X\overset { { C }_{ 6 }{ H }_{ 6 } }{ \underset { Anhydrous \ AlCI }-_{3}{ \longrightarrow } } Y\overset { 1){ CH }_{ 3 }MgBr }{ \underset { II){ H }_{ 3 }{ O }^{ + } }{ \longrightarrow } } Z.\)

(a)

(CH₃)₂ C(OH)C₆H₅

(b)

CH₃CH(OH)C₆H₅

(c)

CH₃CH(OH)CH₂- CH₃

(d)

14.

On reacting with neutral ferric chloride, phenol gives ______.

(a)

red colour

(b)

violet colour

(c)

dark green colour

(d)

no colouration.

15.

on treatment with Con H₂SO₄, predominately gives______.

(a)

(b)

(c)

(d)

16.

The X is _______.

(a)

(b)

(c)

(d)

None of these

17.

On which of the following properties does the coagulating power of an ion depend?

(a)

Both magnitude and sign of the charge on the ion.

(b)

Size of the ion alone

(c)

the magnitude of the charge on the ion alone

(d)

the sign of charge on the ion alone.

18.

Collodion is a 4% solution of which one of the following compounds in alcohol – ether mixture?

(a)

Nitroglycerine

(b)

Cellulose acetate

(c)

Glycoldinitrate

(d)

Nitrocellulose

19.

Hair cream is _____.

(a)

gel

(b)

emulsion

(c)

solid sol

(d)

sol.

20.

Consider the change in oxidation state of Bromine corresponding to different emf values as shown in the diagram below:
\({ BrO }_{ 4 }^{ - }\overset { 1.82V }{ \longrightarrow } { BrO }_{ 3 }^{ - }\overset { 1.5V }{ \longrightarrow } HBrO\overset { 1.595v }{ \longrightarrow } { Br }_{ 2 }\overset { 1.0652V }{ \longrightarrow } Br^{ - }\)
Then the species undergoing disproportional is

(a)

Br₂

(b)

BrO₄^-

(c)

BrO^-₃

(d)

HBrO

21.

During electrolysis of molten sodium chloride, the time required to produce 0.1mole of chlorine gas using a current of 3A is _____.

(a)

55 minutes

(b)

107.2 minutes

(c)

220 minutes

(d)

330 minutes

22.

The button cell used is watches function as follows
Zn (s) + Ag₂O (s) + H₂O (l) ⇌ 2Ag (s) + Zn²⁺ (aq) + 2OH^-(aq) the half cell potentials are Ag₂O (s) + H₂O (l) + 2e^- → 2Ag (s) + 2OH^- (aq) E^o= 34V and Zn (s) → Zn²⁺ (aq) + 2e⁻ E⁰ = 0.76V . The cell potential will be_______.

(a)

0.84V

(b)

1.34V

(c)

1.10V

(d)

0.42V

23.

Which of the following relation is correct for degree of hydrolysis of ammonium acetate?

(a)

\(h=\sqrt { \frac { { K }_{ h } }{ C } } \)

(b)

\(h=\sqrt { \frac { { K }_{ a } }{ K_b } } \)

(c)

\(h=\sqrt { \frac { { K }_{ w } }{ { K }_{ a }.{ K }_{ b } } } \)

(d)

\(h=\sqrt { \frac { { { K }_{ a }.{ K }_{ b } } }{ { K }_{ w } } } \)

24.

The solubility of BaSO₄ in water is 2.42 × 10^-3gL^-1 at 298K. The value of its solubility product(K_sp) will be (Given molar mass of BaSO₄ =233g mol^-1)

(a)

1.08 × 10^-14mol²L^-2

(b)

1.08 × 10^-12mol²L^-2

(c)

1.08 × 10^-10mol²L^-2

(d)

1.08 × 10^-8mol²L^-2

25.

Concentration is expressed in?

(a)

\(\frac { number\ of\ moles/litre }{ time\ in\ sec } \)

(b)

\(\frac { time\ in\ sec }{ number\ of\ moles/litre } \)

(c)

\(\frac { number\ of\ moles/litre }{ volume } \)

(d)

\(\frac { volume }{ number\ of\ moles/litre } \)

26.

(a)

It is a 2 steps reaction, step 1 is slower than step 2

(b)

It is a 2 steps reaction, step 2 is slower than step 1.

(c)

Single step reaction where B is a activated complex

(d)

Single step reaction in which B is a reaction intermediate.

27.

Pick the wrong one among the following

(a)

F₂ - Yellow

(b)

Br₂ - Red

(c)

Cl₂ - Colourless

(d)

I₂- Violet

28.

The empty space between the shaded balls and hollow balls as shown in the diagram is called, _______.

(a)

Hexagonal void

(b)

Octahedral void

(c)

Tetrahedral void

(d)

Double triangular void

29.

SiO₄^4- ion has ____ geometry.

(a)

Triangular

(b)

Tetrahedral

(c)

Linear

(d)

Pentagonal bipyramidal

30.

The general electronic configuration of 4f series of elements can be written as ________.

(a)

[Xe]4f^2-14 5d^0-46s²

(b)

[Xe]4f^2-145d^0-46s¹

(c)

[Xe] 4f^1-145⁰6s¹

(d)

[Xe]4f^2-145d^0-46s¹

31.

Among the following, one does not belong to calcination, Pick the odd one out.

(a)

\({ PBCO }_{ 3 }\overset { \Delta }{ \longrightarrow } PBO+{ CO }_{ 2 }\uparrow \)

(b)

\({ CaCo }_{ 3 }\overset { \Delta }{ \longrightarrow } Cao+{ CO }_{ 2 }\uparrow \)

(c)

\(PbS{ O }_{ 3 }\overset { \Delta }{ \rightarrow } PbO+{ 2SO }_{ 2 }\uparrow \)

(d)

\({ ZnCO }_{ 3 }\overset { \Delta }{ \rightarrow } ZnO+{ CO }_{ 2 }\uparrow \)

32.

Among the following complexes the one which shows zero crystal field stabilisation energy is _______.

(a)

[Mn(H₂O)₆]³⁺

(b)

[Fe(H₂O)₆]³⁺

(c)

[CO(H₂O)₆]²⁺

(d)

[CO(H₂O)₆]³⁺

33.

In a first order reaction x ⟶ y; if k is the rate constant and the initial concentration of the reactant x is 0.1M, then, the half life is_____.

(a)

\(\left( \frac { \log2 }{ k } \right) \)

(b)

\(\left( \frac { 0.693 }{ (0.1)k } \right) \)

(c)

\(\left( \frac { In2 }{ k } \right) \)

(d)

none of these

34.

If ‘a’ is the length of the side of the cube, the distance between the body centered atom and one corner atom in the cube will be_________.

(a)

\(\left( \cfrac { 2 }{ \sqrt { 3 } } \right) a\)

(b)

\(\left( \cfrac { 4 }{ \sqrt { 3 } } \right) a\)

(c)

\(\left( \cfrac { \sqrt { 3 } }{ 4 } \right) a\)

(d)

\(\left( \cfrac { \sqrt { 3 } }{ 2 } \right) a\)

35.

For the reaction, 2NH₃ ⟶ N₂ + 3H₂, if \(\frac { -d[NH_{ 3 }] }{ dt } \) = k₁[NH₃], \(\frac { d[N_{ 2 }] }{ dt } =k_{ 2 }[NH_{ 3 }],\frac { d[{ H }_{ 2 }] }{ dt } \)= k₃[NH₃] then the relation between k₁, k₂ and k₃ is _________.

(a)

k₁= k₂= k₃

(b)

k₁= 3k₂= 2k₃

(c)

1.5k₁= 3k₂= k₃

(d)

2k₁= k₂= 3k₃

36.

Among the following graphs showing variation of rate constant with temperature (T) for a reaction, the one that exhibits Arrhenius behavior over the entire temperature range is _______.

(a)

(b)

(c)

(d)

both (b) and (c)

37.

In calcium fluoride, having the fluorite structure the coordination number of Ca²⁺ ion and F^- Ion are ________.

(a)

4 and 2

(b)

6 and 6

(c)

8 and 4

(d)

4 and 8

38.

A complex in which the oxidation number of the metal is zero is_______.

(a)

K₄[Fe(CN)₆]

(b)

[Fe(CN)₃(NH₃)₃]

(c)

[Fe(CO)₅]

(d)

both (b) and (c)

39.

As per IUPAC guidelines, the name of the complex [Co(en)₂(ONO)Cl]Cl is _______.

(a)

chloro bis ethylenediamine nitrocobalt(III) chloride

(b)

chloridobis(ethane-1, 2-diamine)nitro K-O Cobaltate(III) chloride

(c)

chloridobis(ethane-1, 2-diammine)nitrito K-O Cobalt(II) chloride

(d)

chloridobis(ethane-1, 2-diamine)nitrito K-O Cobalt(III) chloride

40.

Which one of the following is not correct?

(a)

La(OH)₃ is less basic than Lu(OH)₃

(b)

In lanthanoid series ionic radius of Ln³⁺ ions decreases

(c)

La is actually an element of transition metal series rather than lanthanide series

(d)

Atomic radii of Zr and Hf are same because of lanthanide contract

41.

How many moles of I₂ are liberated when 1 mole of potassium dichromate react with potassium iodide?

(a)

(b)

(c)

(d)

42.

Among the transition metals of 3d series, the one that has highest negative \(\left( \frac { M^{ 2+ } }{ M } \right) \) standard electrode potential is _______.

(a)

(b)

(c)

(d)

43.

The compound that is used in nuclear reactors as protective shields and control rods is _________.

(a)

Metal borides

(b)

metal oxides

(c)

Metal carbonates

(d)

metal carbide

44.

Among the following the correct order of acidity is ________.

(a)

HClO₂ < HClO < HClO₃ < HClO₄

(b)

HClO₄ < HClO₂ < HClO < HClO₃

(c)

HClO₃ < HClO₄ < HClO₂ < HClO

(d)

HClO < HClO₂ < HClO₃ < HClO₄

45.

An element belongs to group 15 and 3^rdperiod of the periodic table, its electronic configuration would be_______.

(a)

1s² 2s² 2p⁴

(b)

1s² 2s² 2p³

(c)

1s² 2s² 2p⁶ 3s² 3p²

(d)

1s² 2s² 2p⁶ 3s² 3p³

46.

The repeating unit in silicone is_______.

(a)

SiO₂

(b)

(c)

(d)

47.

In diborane, the number of electrons that accounts for banana bonds is ________.

(a)

six

(b)

two

(c)

four

(d)

three

48.

Which of the following is not true with respect to Ellingham diagram?

(a)

Free energy changes follow a straight line. Deviation occurs when there is a phase change.

(b)

The graph for the formation of CO₂ is a straight line almost parallel to free energy axis.

(c)

Negative slope of CO shows that it becomes more stable with increase in temperature.

(d)

Positive slope of metal oxides shows that their stabilities decrease with increase in temperature.

49.

Zinc is obtained from ZnO by________.

(a)

Carbon reduction

(b)

Reduction using silver

(c)

Electrochemical process

(d)

Acid leaching

50.

Which one of the following reaction represents calcinations?

(a)

\(2Zn+{ O }_{ 2 }\rightarrow 2ZnO\)

(b)

\(2ZnS+3O_{ 2 }\rightarrow 2ZnO+2SO_{ 2 }\)

(c)

\(MgCO_{ 3 }\rightarrow MgO+CO_{ 2 }\)

(d)

Both (a) and (c)

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Answers Key:

Multiple Choice Question

50 x 1 = 50

(a)
i & ii

(d)
both (a) & (b)

(a)
Cr

(a)
K_a = α²C

(d)
the sugar component in RNA is ribose and the sugar component in DNA is 2’-deoxyribose

(a)
H₃PO₂ and H₂O

10.

11.

(d)
Wolf kishner reduction

12.

13.

14.

(b)
violet colour

15.

According to Saytzeff rule.

16.

Hydroboration - Anti Markownikoff product
CH₃– CH₂ –CH₂ – CH₂– CH₂– OH

17.

(a)
Both magnitude and sign of the charge on the ion.

18.

Pyroxylin(nitro cellulose)

19.

Emulsion-Dispersed phase
Dispersion meduun -liquid

20.

(E_cell)_A = -1.82 + 1.5 = -0.32V
(E_cell)_B = -1.5 + 1.595 = + 0.095V
(E_cell)_C = -1.595 + 1.0652 = -0.529V
The species undergoing disproportionation is HBrO

21.

mass of 1 mole of CI₂ gas = 71
∴ mass of 0.1 mole of Cl₂ gas = 7.1 g mol^-1
m = Zlt
t = m/ZI
\(= \frac{7.1}{\frac{71}{2 \times 96500} \times 3}\) (2Cl^- ➝ Cl₂+ 2e^-)
\(= \frac{2 \times 96500 \times 7.1}{71 \times 3}\)
= 6433.33s = 107.2 min

22.

Anodic Oxidation: (Reverse the given reaction)
(E^o_ox) = 0.76 V Cathodic reduction
E^o_cell= (E^o_ox)+ (E^o_red)
= 0.76 + 0.34 = 1.1 V

23.

24.

BaSO₄ ⇌ Ba²⁺ + SO₄^2-
K_sp = (s) (s)
K_sp = (s)²
= (2.42 × 10^-3gL^-1)²
\(=\frac{2.42 \times 10^{-3} gL^{-1}}{233 \text{ g mol}^{-1}}\)
= (0.01038 x 10^-3)²
= (1.038 x x 10^-5)²
= 1.077 x 10^-10
= 1.08 × 10^-10mol²L^-2

25.

(a)
\(\frac { number\ of\ moles/litre }{ time\ in\ sec } \)

26.

(a)
It is a 2 steps reaction, step 1 is slower than step 2

27.

28.

(b)
Octahedral void

29.

(b)
Tetrahedral

30.

(a)
[Xe]4f^2-14 5d^0-46s²

31.

32.

(b)
[Fe(H₂O)₆]³⁺

33.

\(k=\frac { 1 }{ t } ln \frac { \left[ { A }_{ 0 } \right] }{ \left[ A \right] } \)
[A₀] = 0.1: [A] = 0.05
\(k= \left[ \frac { 1 }{ t _{1/2}} \right] ln\left[ \frac { { 0.1 } }{ 0.05 }\right] \)
\(k= \left[ \frac { 1 }{ t _{1/2}} \right] ln (2)\)
t_1/2 = In(2)/K

34.

If a is the length of the side, then the length of the leading diagonal passing through the body centered atom is \(\sqrt{3a} \)
Required distance = \(\left( \cfrac { \sqrt { 3 } }{ 2 } \right) a\)

35.

\(Rate=\frac { -1 }{ 2 } \frac { d[NH_3] }{ dt } \)
\(\frac { -d\left[ { N }_{ 2 } \right] }{ dt } =\frac { 1 }{ 3 } \frac { d\left[ { H}_{ 2 } \right] }{ dt } \)
\(=\frac { 1 }{ 2 } { k_1\left[ { NH}_{ 3 } \right] } = { k_2 \left[ { NH}_{ 3 } \right] }=\frac { 1 }{ 3 } { k_3\left[ { NH}_{ 3 } \right] } \)
[3/2] k₁ = 3k₂ = k₃
1.5k₁= 3k₂= k₃

36.

\(k=A{ e }^{ -\left( \frac { { E }_{ a } }{ RT } \right) }\)
In k = In A - \({ \left( \frac { { E }_{ a } }{ R } \right) }\) \(\left( \frac { 1 }{ T } \right) \)
This equation is of the form of a straight line y = mx+c
A plot of In k Vs \(\left( \frac { 1 }{ T } \right) \) gives a straight line with a negative slope.

37.

38.

a) Fe²⁺ b) Fe³⁺ c) Fe⁰

39.