An amphoteric  oxide among the following is-

1. CO₂

2. CO

3. SnO₂

4. CaO

In B₂H₆ 

(1) there is direct boron-boron bond

(2) the structure is similar to that of C₂H₆

(3) the boron atoms are linked through hydrogen bridges

(4) all the atoms are in one plane

From the B₂H₆ all the following can be prepared except:

(1) H₃BO₃

(2) [BH₂(NH₃)₂]+ [BH₄]-

(3) B₂(CH₃)₆

(4) NaBH₄

The correct order of Lewis acid strength of trihalides of boron is:

1. BCl₃ > BBr₃ > BF₃ > BI₃

2. BF₃ < BBr₃ < BCl₃ < BI₃

3. BF₃ < BCl₃ < BBr₃ < BI₃

4. BF₃ >BCl₃ > BBr₃ > BI₃

The correct order of ease of hydrolysis is :

1. CCl₄ < SiCl₄ < PCl₅ < AlCl₃

2. AlCl₃ < CCl₄ < PCl₅ < SiCl₄

3. CCl₄ < AlCl₃ < PCl₅ < SiCl₄

4. CCl₄ < AlCl₃ < SiCl₄ < PCl₅

Pick the correct statement :

(1) Borax is white crystalline solid containing [B₄O₅(OH)₄]^2- units

(2) Aqueous solution of borax is acidic in nature.

(3) Cobalt gives green colour in borax bead test.

(4) All are incorrect.

The element among the following that does not show inert pair effect is-

Which of the following compounds is the weakest Lewis acid?

1. BF₃

2.  BCl₃

3. BBr₃

4.  BI₃

It is because inability of ns² electrons of the valence shell to participate in bonding that

1. Sn²⁺ is reducing while Pb⁴⁺ is oxidising agent

2. Sn²⁺ is oxidising while Pb⁴⁺ is reducing agent

3. Sn²⁺ and Pb²⁺ are both oxidising and reducing agent

4. Sn⁴⁺ is reducing while Pb⁴⁺ is oxidising agent

The number of carbon atoms per unit cell of diamond unit cell is:-

1. 4

2. 8

3. 6

4. 1