The incorrect statement regarding allotropes/allotropy is :

1.	Allotropy is the existence of an element in more than one form.
2.	Allotropes have the same chemical properties but different physical properties.
3.	Diamond and graphite are allotropes of carbon.
4.	None of the above.

The correct statement(s) regarding thallium is/are :

1. Thallium displays both +1, and +3 oxidation states.

2. It resembles group 1 metals in some reactions.

3. Thallium only shows a +1 oxidation state.

4. Both (1) and (2) 

Which statement among the following is incorrect?

Borax when heated strongly gives

1. ${\mathrm{Na}}_{}{\mathrm{BO}}_2$

2. ${\mathrm{B}}_2{\mathrm{O}}_3$

3. ${\mathrm{Na}}_2{\mathrm{O}}_2$

4. Both (1) and (2)

The correct statement(s) regarding diborane and boric acid is/are-

1. Diborane has two 3c-2e^- bonds.

2. Boric acid has a layered structure.

3. Four 2c-2e^- bonds are present in diborane.

4. All of the above

The incorrect statement among the following options is-

The correct statement(s) among the following options is/are:

Aluminum trifluoride is insoluble in anhydrous HF but dissolves on addition of NaF because:

The complex formed on reaction of Sodium hexafluoroaluminate(III) with BF₃ is -

1. $\mathrm{Na}\left[{\mathrm{BF}}_4\right]$

2. ${\mathrm{Na}}_2\left[{\mathrm{BF}}_4\right]$

3. $\mathrm{Na}{\left[{\mathrm{BF}}_4\right]}_2$

4. None of the above 

The correct statement(s) regarding Lead compounds is/are:

1. Lead (II) reacts with Cl₂ to give PbCl₄

2. Lead (IV) chloride is highly stable towards heat.

3. Lead is not known to form an iodide, PbI₄

4. Both (1) and (3)