Which of the following statements about aluminium are correct?

The correct statement(s) regarding diborane and boric acid is/are :

1. Diborane has two 3c-2e^- bonds.

2. Boric acid has a layered structure.

3. Four 2c-2e^- bonds are present in diborane.

4. All of the above

Assertion: The B–X bond lengths in boron trihalides (BX₃) are shorter than those expected for
                   pure B–X single bonds.

Reason: $\mathrm{p\pi –p\pi \; back-bonding\; occurs\; between\; the\; halogen\; atoms\; and\; the\; boron\; atom\; in\; BX₃.}$

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.

A compound X, of boron, reacts with ${\mathrm{NH}}_3$ on heating to give another compound Y which is called inorganic benzene. The compound X can be prepared by treating ${\mathrm{BF}}_3$ with Lithium aluminium hydride. The compounds X and Y are represented by the formulas -

Find the correct nature of boric acid, H₃BO₃:

1. Protic acid.

2. Weak monobasic acid.

3. Lewis acid.

4. Both '2' and '3'

${\mathrm{}}_{}$
Which of the following correctly describes the acidic nature of H₃BO₃?

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.

Which of the following is primarily responsible for the formation of a layered
polymeric structure in solid boric acid (H₃BO₃)?

1. Its acidic nature.

2. The presence of hydrogen bonds.

3. Its monobasic nature.

4. Its trigonal planar geometry.

Which option correctly represents the two H–B–H bond angles found in diborane?

1. $60°,$ $120°$

2. $97°,120°$

3. $97°,150°$

4. $120°,$ $180°$

What is the effect of heating H₃BO₃ at 370 K and above?

1. Orthoboric acid changes to metaboric acid.

2. Metaboric acid changes to boric oxide.

3. Both '1' and '2'

4. Neither '1' nor '2'

Quartz is made of silicon and oxygen joined in a network arrangement that is similar to:

1. Diamond

2. Graphite

3. $O_2$

4. None of the above