AlF₃ is soluble in HF only in the presence of KF. It is due to the formation of _________.

(a)

K₃[AIF₃H₃]

(b)

K₃[AiF₆]

(c)

AIH₃

(d)

K[AIF₃H]

Thermodynamically the most stable form of carbon is________.

(a)

Diamond

(b)

graphite

(c)

Fullerene

(d)

none of these

Lewis acid character of boron trihalides is as a follows _______.

(a)

BF₃ > BCl₃ > BBr₃ > BI₃

(b)

BCI₃ > BF₃ > BBr₃ > BI₃

(c)

BI₃ > BBr₃ > BCl₃ > BF₃

(d)

BI₃ > BF₃ > BCl₃ > BBr₃

Select the incorrect statement regarding B₂H₆.

(a)

It contains B-B ionic bond

(b)

Each boron is Sp³ hybridised

(c)

It has two types of hydrogen bonds

(d)

it is used as a reducing agent

The stability of +1 oxidation state among Al, Ga, In and Tl increases in sequence _______.

(a)

TI < In < Ga < Al

(b)

In < TI < Ga < Al

(c)

Ga < In < Al < TI

(d)

Al < Ga < In < TI

Which one of the following compounds has similar structure to that of graphite?

(a)

Boron nitride

(b)

Boron Carbide

(c)

Aluminium Carbide

(d)

Aluminium Oxide

Chemical formula of phosgene is_______.

(a)

COCl₂

(b)

CaOCl₂

(c)

CaCO₃

(d)

COCI

Graphite has _______.

(a)

2-d sheet structure

(b)

Vander waals force between successive layers of carbon sheets

(c)

Sp² hybridised carbon linked with other three carbon atoms in hexagonal planar structure

(d)

all the above

SiO₄^4- ion has ____ geometry.

(a)

Triangular

(b)

Tetrahedral

(c)

Linear

(d)

Pentagonal bipyramidal

Which one is correct statement for zeolite?

(a)

Zeolites are aluminosilicates having three dimensional framework

(b)

Hydrate zeolites are used as ion exchangers in hardening of soft water

(c)

Zeolites are alumino silicates

(d)

all the above

Which of the following oxide is amphoteric?

(a)

SiO₂

(b)

CO₂

(c)

SnO₂

(d)

CaO

Identify the electron - deficient species

(a)

(BH₃)₂

(b)

(SiH₃)₂

(c)

PH₃

(d)

(CH₃)₂

Which of the following statements about H₃BO₃ is not correct?

(a)

It has a layer structure in which planar BO₃ units are joined by H-bonds

(b)

It is a strong tribasic acid

(c)

It is prepared by acidifying an aqueous solution of borax

(d)

It does not act as proton donor but acts as lewis acid by accepting hydroxyl ion

Boron compounds behave as Lewis acid, because of their _______.

(a)

ionisation property

(b)

acidic nature

(c)

covalent nature

(d)

electron deficient nature

In graphite electrons are _______.

(a)

localised on each C-atom

(b)

localised on every third C-atom

(c)

delocalised within the layer

(d)

present in anti-bonding orbital