Which is incorrect?

1. $Pb{l}_2+l_2\to Pb{l}_4$

2. In diborane 'B' is $s{p}^3$ hybridised

3. Pyrosilicate contains $S{i}_2{O_7}^{6-}$

4. Borax has 8 mole of water of crystallisation per mole

 

The dissolution of $Al{\left(OH\right)}_3$ by a solution of NaOH results in the formation of

1. ${\left[Al{\left(H_{2}O\right)}_4\left(OH\right)\right]}^{2+}$

2. ${\left[Al{\left(H_{2}O\right)}_2{\left(OH\right)}_4\right]}^{-}$

3. $\left[Al{\left(H_{2}O\right)}_3{\left(OH\right)}_3\right]$

4. $\left[Al{\left(H_{2}O\right)}_6{\left(OH\right)}_3\right]$

Which of the following is the correct order of first ionisation energy of group-14 elements?

1. $C<Si<Ge<Sn<Pb$

2. $C>Si>Ge>Sn>Pb$

3. $C>Si>Ge>Sn<Pb$

4. $C>Si<Ge>Sn<Pb$

Compound (B) is

1. $B_2{H}_6.2N{H}_3$

2. $B_3{N}_3{H}_6$

3. ${\left(BN\right)}_x$

4. $H_{3}B{O}_3$

Silica reacts with

1. $H_{2}S{O}_4$

2. $HN{O}_3$

3. HF

4. HCl

The correct statement is-

1. Inorganic benzene is less reactive than benzene

2. The hybridisation of two boron atom in borax is $s{p}^2$ and the other two boron atom is $s{p}^3$

3. Fullerene $\left(C_{70}\right)$ has 20 six membered rings  

4. All of the above

The maximum number of atoms in dibrone $\left(B_2{H}_6\right)$ lying in the same plane is

1. 8

2. 6

3. 4

4. 7

The purest and thermodynamically most stable allotrope of carbon respectively is

1. Fullerene, diamond 

2. Graphite, diamond

3. Fullerene, graphite

4. Diamond, fullerene

               $Al{F}_3+\underset{Excess}{KF}\to \overline{)A}$
$B{F}_3+\underset{Excess}{KF} \to \overline{)B}$

Compound $\overline{)A} and \overline{)B}$ are respectively

1. $K_{3}Al{F}_6 and KB{F}_4$

2. $KAl{F}_4 \& K_{3}B{F}_6$

3. $K_{3}Al{F}_6 and K_{3}B{F}_6$

4. $K_{2}Al{F}_4 \& KB{F}_4$

Boranes have general formula

1. $B_n{H}_{n+4}$

2. $B_n{H}_{n+6}$

3. $B_n{H}_{2n+2}$

4. Both (1) & (2)