In a Borax bead test, which compound is formed: 

1. Orthoborate

2. Metaborate

3. Double oxide

4. Tetraborate

$Pb{O}_2$ $\to$ $PbO$ $$ $$ $$ $$ $$ $$ $$ $$ $$ $$ $$ $$ $$ $$ $$ $$ $$ $$ $$ $$ $∆G_{298}$ $<0$
$Sn{O}_2\to SnO$ $$ $$ $$ $$ $$ $$ $$ $$ $$ $$ $$ $$ $$ $$ $$ $$ $$ $$ $$ $$ $$ $$ $∆G_{298}$ $>$ $0$

The most probable oxidation state of Pb & Sn will be:

1. ${\mathrm{Pb}}^{+4},$ ${\mathrm{Sn}}^{+4}$

2. ${\mathrm{Pb}}^{+4}$ $,$ ${\mathrm{Sn}}^{+2}$

3. ${\mathrm{Pb}}^{+2}$ $,$ ${\mathrm{Sn}}^{+2}$

4. ${\mathrm{Pb}}^{+2}$ $,$ ${\mathrm{Sn}}^{+4}$

BCl₃  has higher stability than ${\mathrm{TlCl}}_3$, because -

Boron trifluoride behaves as a Lewis acid because -

1. Boron trifluoride is electron-rich.

2. Boron trifluoride is electron-deficient.

3. Boron trifluoride is highly stable.

4. None of these.

The correct statement among the following regarding behavior of ${\mathrm{BCI}}_3$ $\mathrm{and}$ ${\mathrm{CCI}}_4$ in water is -

Boric acid is a-

1. Protic acid.

2. Weak monobasic acid.

3. Lewis acid.

4. Both '2' and '3'

The effect of heating Boric acid at 370 K or above is -

1. Orthoboric acid changes to metaboric acid.

2. Metaboric acid changes to boric oxide.

3. Both '1' and '2'

4. Neither '1' nor '2'

The shapes of ${\mathrm{BF}}_3 \mathrm{and} \mathrm{B}{{\mathrm{H}}_4}^{-}$ and the hybridization of boron in these species are respectively -

1. ${\mathrm{BF}}_3$ - triangular geometry, ${\mathrm{sp}}^2$; $\mathrm{B}{{\mathrm{H}}_4}^{-}$- tetrahedral, ${\mathrm{sp}}^3$

2. ${\mathrm{BF}}_3$ - tetrahedral, ${\mathrm{sp}}^2$; $\mathrm{B}{{\mathrm{H}}_4}^{-}$ - triangular geometry, ${\mathrm{sp}}^3$

3.  ${\mathrm{BF}}_3$ - tetrahedral, ${\mathrm{sp}}^3$ ; $\mathrm{B}{{\mathrm{H}}_4}^{-}$ - triangular geometry, $s{p}^3$

4. ${\mathrm{BF}}_3$ - tetrahedral, ${\mathrm{sp}}^2$ ; $\mathrm{B}{{\mathrm{H}}_4}^{-}$ - triangular geometry, ${\mathrm{sp}}^2$

Reaction(s) that justify the amphoteric nature of aluminum is-

$1. 2\mathrm{Al}\left(\mathrm{s}\right) + 6\mathrm{HCl}\left(\mathrm{aq}\right) \to 2{\mathrm{Al}}^{+3}\left(\mathrm{aq}\right) + 6{\mathrm{Cl}}^{-}\left(\mathrm{aq}\right) + 3{\mathrm{H}}_2\left(\mathrm{g}\right)$​

$2. 2\mathrm{Al}\left(\mathrm{s}\right) + 2\mathrm{NaOH}\left(\mathrm{aq}\right) + 6{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right) \to 2\mathrm{Na}\left[\mathrm{Al}{\left(\mathrm{OH}\right)}_4{]}^{-}\right(\mathrm{aq}) +3{\mathrm{H}}_2(\mathrm{g})$​

3. Both '1' and '2'

4. Neither '1' nor '2'

The electron-deficient compound among the following is -

1. ${\mathrm{SiCl}}_4$

2. ${\mathrm{BCl}}_3$

3. ${\mathrm{PCl}}_3$

4. $\mathrm{ICl}$