To get an n-type semiconductor from silicon, it should be doped with a substance with valence.......................... .

1

(a)

2

(b)

1

(c)

3

(d)

5

Colligative properties depend on .............. .

1

(a)

the nature of the solute particles dissolved in solution

(b)

the number of solute particles in solution

(c)

the physical properties of the solute particles dissolved in solution

(d)

the nature of solvent particles

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

1

(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

Mark the incorrect statements.

1

(a)

Catalyst provides an alternative pathway to reaction mechanism

(b)

Catalyst raises the activation energy

(c)

Catalyst lowers the activation energy

(d)

Catalyst alters enthalpy change of the reaction.

In physisorption, adsorbent does not show specificity for any particular has because........................ .

1

(a)

involved van der Waals forces are universal

(b)

gases involved behave like ideal gases

(c)

enthalpy of adsorption is low

(d)

it is a reversible process

Electrolytic refining is used  to purify which of the following metals?

1

(a)

Cu and Zn

(b)

Ge and Si

(c)

Zr and Ti

(d)

Zn and Hg

Which of the following acids forms three series of salts?

1

(a)

H₃PO₂

(b)

H₃BO₃

(c)

H₃PO₄

(d)

H₃PO₃

There are 14 elements in actinoid series. Which of the following elements does belong to this series ?

1

(a)

U

(b)

Np

(c)

Tm

(d)

Fm

The colour of the coordination compounds depends on the crystal field splitting. What will be the correct order of absorption of wavelength of light in the visible region for the complexes, [Co(NH₃)₆]³⁺, [Co(CN)₆]^3-, [Co(H₂O)₆]³⁺

1

(a)

[Co(CN)₆]^3- > [Co(NH₃)₆]³⁺ >  [Co(H₂O)₆]³⁺

(b)

[Co(NH₃)₆]³⁺ >  [Co(H₂O)₆]³⁺ > [Co(CN)₆]^3- 

(c)

[Co(H₂O)₆]³⁺ >  [Co(NH₃)₆]³⁺ > [Co(CN)₆]^3-

(d)

 [Co(CN)₆]^3- >   [Co(NH₃)₆]³⁺ > [Co(H₂O)₆]³⁺

Ethylidene chloride is a/an ............

1

(a)

vic-dihalide

(b)

gem-dihalide

(c)

allylic halide

(d)

vinylic halide

How many alcohols with molecular formula C₄H₁₀O are chiral in nature?

1

(a)

1

(b)

2

(c)

3

(d)

4

Cannizzaro's reaction is not given by ____________.

1

(a)

(b)

(c)

HCHO

(d)

CH₃CHO

In the nitration of benzene using a mixture of conc. H₂SO₄ and conc.HNO₃, the species which initiates the reaction is......................... .

1

(a)

NO₂

(b)

NO⁺

(c)

\({ NO }_{ 2 }^{ + }\)

(d)

\({ NO }_{ 2 }^{ - }\)

Dinucleotide is obtained by joining two nucleotides together by phosphodiester linkage. Between which carbon atoms of pentose sugars of nucleotides are these linkages present ?

1

(a)

5' and 3'

(b)

1' and 5'

(c)

5' and 5'

(d)

3' and 3'

Which of the following is not a semisynthetic polymer?

 

1

(a)

cis-Polyisoprene

(b)

Cellulose nitrate

(c)

Cellulose acetate

(d)

Vulcanised rubber