Find the amphoteric oxide among the following.

$$Which of the following best explains the difference in hydrolytic behaviour between CCl₄ and SiCl₄?

1.  Carbon cannot expand its octet but silicon can expand.

2. The electronegativity of carbon is higher than that of silicon

3. The ionization potential of carbon is higher than that of silicon

4.  Carbon forms double and triple bonds, but silicon does not

Why is CO₂ more effective than N₂ in extinguishing fires?

1. It is non-combustible.

2. It forms non-combustible products with burning substances.

3. It has a higher density than nitrogen.

4. It is chemically more reactive than nitrogen.

 Which among the following is a gas?

1. $B{F}_3$

2. $BC{l}_3$

3. $BB{r}_3$

4. $B{I}_3$

Why is BF₃ a weaker Lewis acid than BCl₃?

1. High electronegativity of fluorine

2. Presence of three-center–two-electron bonds

3. pπ–dπ back-bonding

4. pπ–pπ back-bonding

Which of the following products is formed when orthoboric acid is heated to red heat?

Which of the following products is formed when boric acid, H₃BO₃, is heated to about 150°C?

1. ${\mathrm{B}}_2{\mathrm{O}}_3$

2. ${\mathrm{H}}_2{\mathrm{B}}_4{\mathrm{O}}_7$

3. ${\mathrm{HBO}}_2$

4. ${\mathrm{H}}_2{\mathrm{BO}}_3$

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

1. $60°,$ $120°$

2. $97°,120°$

3. $97°,150°$

4. $120°,$ $180°$

Which of the following carbides produces propyne on hydrolysis?

1. ${\mathrm{Al}}_4{\mathrm{C}}_3$

2. ${\mathrm{Mg}}_2{\mathrm{C}}_3$

3. ${\mathrm{B}}_4\mathrm{C}$

4. ${\mathrm{La}}_4{\mathrm{C}}_3$

Find the most volatile compound among the following.

1.  ${\mathrm{CH}}_4$

2.  ${\mathrm{SiH}}_4$

3.  ${\mathrm{GeH}}_4$

4.  ${\mathrm{SnH}}_4$