In the reaction $2B+6HN{O}_3\to \overline{)A}+6N{O}_2$

The product $\overline{)A}$ is

1. $B_2{O}_3$

2. $2HB{O}_3$

3. $2H_{3}B{O}_2$

4. $2H_{3}B{O}_3$

Which of the following is not correct about silicones?

1. They are chemically inert and water-repelling in nature

2. Lower silicons are oily liquids

3. They are used in making waterproof clothes

4. Good electrical conductor

Which of the following halide is least stable and has doubtful existence?

1. $CC{l}_4$

2. $PbC{l}_2$

3. $SiC{l}_4$

4. $Pb{l}_4$

Which is not correct about $B{F}_3$?

1. It is stronger Lewis acid than $BC{l}_3$

2. It does not form dimer like $A{l}_{2}C{l}_6$

3. It can combine with $F^{-}$ ion to form $B{F}_4^{-}$ ion

4. It contains back $\mathrm{\pi }$- bonding 

Which of the following regarding Boron nitride is correct?

1. Its structure is similar to diamond in which both 'B' and 'N' $s{p}^3$ hybridised

2. Its structure is similar to graphite in which both 'B' and 'N' $s{p}^2$ hybridised

3. BN posses linear structure

4. BN is ionic, hence non-directional in nature

Which of the following option is correct?

Correct order of thermal stability of hydride of group 14 is

1. $C{H}_4<Si{H}_4<Ge{H}_4<Sn{H}_4$

2. $C{H}_4>Si{H}_4>Sn{H}_4>Ge{H}_4$

3. $Sn{H}_4<Ge{H}_4<Si{H}_4<C{H}_4$

4. $C{H}_4<Si{H}_4>Ge{H}_4>Sn{H}_4$

The number of five-membered and six-membered rings in $C_{70}$ fullerene respectively is 

1. 12, 20

2. 12, 25

3. 15, 20

4. 10, 20

Linear silicones have the repeating unit of

1. $\left(RSiO\right)$

2. $\left(RSi{O}_2\right)$

3. $\left(R_{2}SiO\right)$

4. $\left(R_{2}Si{O}_2\right)$

${\left[{\mathrm{SIF}}_6\right]}^{2-}$ exists but ${\left[SiC{l}_6\right]}^{2-}$ does not exist because 

1. Smaller size of F than Cl

2. F is more electronegative than Cl 

3. Interaction of F lone pair electrons with d orbital of silicon is weaker than that of Cl lone pair electron

4. All of the above