Assertion: Boron always forms a covalent bond.

Reason: Boron has a diagonal relationship with silicon.

1. Both Assertion & Reason are true and the reason is the correct explanation of the assertion.
2. Both Assertion & Reason are true but the reason is not the correct explanation of the assertion.
3. Assertion is a true statement but Reason is false.
4. Both Assertion and Reason are false statements.

Assertion: B-X bond length in ${\mathrm{BX}}_3$ is shorter than the expected value.

Reason: $p\mathrm{\pi }-\mathrm{p\pi }$ back bonding occurs between B and X.

1. Both Assertion & Reason are true and the reason is the correct explanation of the assertion.
2. Both Assertion & Reason are true but the reason is not the correct explanation of the assertion.
3. Assertion is a true statement but Reason is false.
4. Both Assertion and Reason are false statements.

Assertion: The total number of coordinate bonds and covalent bonds in borazine is 3 and 12 respectively.

Reason: Its structure is similar to benzene.

1. Both Assertion & Reason are true and the reason is the correct explanation of the assertion.

2. Both Assertion & Reason are true but the reason is not the correct explanation of the assertion.

3. Assertion is a true statement but Reason is false.

4. Both Assertion and Reason are false statements.

White fumes appear around the bottle of anhydrous AlCl₃. This is due to :

1. Formation of Al(OH)₃

2. Dimerisation of AlCl₃

3. Hydrolysis of AlCl₃ gives HCl gas

4. Adsorption of moisture 

The element among the following that does not show the inert pair effect is:

1. Al

2. Sn

3. Pb

4. Tl

${\mathrm{H}}_3{\mathrm{BO}}_3$ is -

1. A Monobasic acid and a weak Lewis acid.

2. A Monobasic and a weak Bronsted acid..

3. A Monobasic and a strong Lewis acid.

4. A Tribasic and a weak Bronsted acid.

The most characteristic oxidation state for lead and tin is, respectively,:

1. +4, +2

2. +2, +4

3. +4, +4

4. +2, +2

An anion present in the chain structure silicate is -

1. ${\mathrm{Si}}_2{\mathrm{O}}_7^{6-}$

2. ${\left({\mathrm{Si}}_2{\mathrm{O}}_5^{2-}\right)}_{\mathrm{n}}$

3. ${\left({\mathrm{SiO}}_3^{2-}\right)}_{\mathrm{n}}$

4. ${\mathrm{SiO}}_4^{4-}$

${\mathrm{B}}_2{\mathrm{H}}_6$ can't be prepared by -

1. ${\mathrm{NaBH}}_4$ $$ $+$ ${\mathrm{I}}_2$ $\to$

2. ${\mathrm{BF}}_3$ $$ $+$ $\mathrm{NaH}$ $\to$

3. ${\mathrm{B}}_3{\mathrm{N}}_3{\mathrm{H}}_6$ $$ $+$ ${\mathrm{H}}_2\mathrm{O}$ $\to$

4. ${\mathrm{Mg}}_3{\mathrm{B}}_2$ $+$ $\mathrm{dil}$ $\mathrm{HCl}\to$

${\mathrm{Na}}_2{\mathrm{B}}_4{\mathrm{O}}_7\cdot 10{\mathrm{H}}_2\mathrm{O}<mspace\; width="1em"></mspace>\underset{∆}{\overset{{740}^{\circ }\mathrm{C}}{\to }}<mspace\; width="1em"></mspace>2{\mathrm{NaBO}}_2+\left(\mathrm{X}\right)+10{\mathrm{H}}_2\mathrm{O}$
$\left(\mathrm{X}\right)+{\mathrm{CaF}}_2+{\mathrm{H}}_2{\mathrm{SO}}_4⟶\mathrm{Y}+{\mathrm{CaSO}}_4+{\mathrm{H}}_2\mathrm{O}$
$\left(\mathrm{Y}\right)+{\mathrm{NaBH}}_4⟶\left(\mathrm{Z}\right)+{\mathrm{NaBF}}_4$

Select the incorrect statement regarding compounds (X), (Y) and (Z).

1.  Compound (X) is ${\mathrm{B}}_2{\mathrm{O}}_3$ and compound (Z) contains two 3C - 2e bonds

2.  Compound (X) is ${\mathrm{B}}_2{\mathrm{O}}_3$ and compound (Y) contains one 3C - 2e bonds 

3.  Compound (Y) is Lewis acid and stable due to $p\pi -p\pi$ back bonding

4.  Compound (Z) reacts with excess of ${\mathrm{NH}}_3$ at high temperature gives inorganic graphite