The least basic compound is:

1. BiH₃

2. AsH₃

3. PH₃

4. NH₃

Incorrect statement about red phosphorus is:

1. It is hard and crystalline.

2. It is poisonous.

3. It is less reactive than white phosphorus.

4. It is insoluble in water.

Which element exhibits the highest catenation property?

1. Phosphorus

2. Nitrogen

3. Antimony

4. Bismuth

PCl₅ acts as

1. Reducing agent

2. Oxidising agent

3. Dehydrating Agent

4. None of the above.

The electron gain enthalpy values for O → O^– and O → O^2– are –141 and 702 kJ  mol^-1 , respectively. The correct statement about the formation of oxides is-

In which compound does phosphorous have the lowest oxidation state?

1. H₃PO₃ 

2. PCl₃ 

3. Ca₃P₂ 

4. POF₃

 A xenon fluoride that does not exist is:

1. XeF₄
2. XeF₂
3. XeF₃
4. XeF₆

XeF₄ is isostructural with :

1. ${\mathrm{ICl}}_4^{-}$       

2. ${\mathrm{IBr}}_2^{-}$                   

3. ${\mathrm{BrO}}_3^{-}$

4. ${\mathrm{ICl}}_3^{-}$

Which of the following is incorrect regarding noble gases?

1. The atomic radii corresponds to van der Waal’s radii.

2. They have the largest size in a period.

3. They are also called inert gases.

4. They combine to form molecules.

In solid-state, PCl₅ exists as: