Which of the following oxide is most acidic

(1) Na₂O

(2) Al₂O₃

(3) P₂O₅

(4) SO₃

The least acidic oxide among the following is:

1. P₄O₆ 

2. P₄O₁₀ 

3. As₄O₆ 

4. As₄O₁₀ 

Moist ammonia gas is dried over

(1) P₂O₅

(2) Anhydrous CaCl₂

(3)Quick lime

(4)Conc. H₂SO₄

In the compounds of the type POX₃, the P atom multiple bond is of the type

(1) $p\mathrm{\pi }-\mathrm{p\pi }$

(2) $d\mathrm{\pi }-\mathrm{d\pi }$

(3) $p\mathrm{\pi }-\mathrm{d\pi }$

(4) None of these

Which of the following statement is not true for phosphorus?

The basicity of the acids H₃PO₂, H₃PO₃, H₃PO₄  and H₄P₂O₇ are respectively

(A) 1,2,3,7

(B) 2,3,4,7

(C) 1,2,3,4

(D) 1,2,3,5

Which of the following flourides has the least capacity as fluoride ion acceptor

(1)AsF₅

(2) SbF₅

(3) PF₅

(4) None of these

The ionic character of H-X is highest in

(1) HBr

(2) HI

(3) HF

(4)HCl

The strongest acid is

(1) H₃PO₂ 

(2) H₃PO₃ 

(3) H₄P₂O₇ 

(4) H₃PO₄ 

The strength of halogen acids, HF, HCl, HBr, and HI varies in the order

1. HF>HCl>HBr>HI

2. HF>HBr>HI>HCl

3. HBr>HI>HCl>HF

4. HI>HBr>HCl>HF