An oxyacid among the following that contains both P-H and P-P bonds simultaneously is:

1. H₄P₂O₅

2. H₄P₂O₇

3. H₄P₂O₆

4. None of the above

Oxidation of nitrogen among the following reactions is indicated by -
1. \(\mathrm{N}_2 \rightarrow 2 \mathrm{NH}_3 \)
2. \(\mathrm{N}_2 \mathrm{O}_4 \rightarrow 2 \mathrm{NO}_2 \)
3. \(\mathrm{NO}_3{ }^{-} \rightarrow \mathrm{N}_2 \mathrm{O}_5 \)
4. \(\mathrm{NO}_2^{-} \rightarrow \mathrm{NO}_3^{-}\)

Which of the following has been arranged in order of decreasing bond dissociation energy:

1. P-O>Cl-O>S-O

2. P-O>S-O>Cl-O

3. S-O>Cl-O>P-O

4. Cl-O>S-O>P-O

Among the following reactions,  N₂ is not generated by heating:

1. (NH₄)₂Cr₂O₇

2. NH₄Cl + NaNO₂

3. NH₄Cl + CaO

4. Ba(N₃)₂

Incorrectly matched characteristic is:

1. S₈: covalent lattice

2. P₄: tetrahedron

3. S₅^2-: zigzag

4. SiO₂: Covalent lattice

Which of the following is the correct statement?

1. F₂ has higher dissociation energy than Cl₂

2. F has higher electron affinity than Cl

3. HF is stronger acid than HCl

4. Boiling point increases down the group in halogens

The partial hydrolysis of one mole of peroxodi-sulphuric acid produces  

Iodine on reaction with concentrated nitric acid forms:

1. HOI

2. HI

3. HIO₃

4. HIO₄

The formation of ${\mathrm{PH}}_4^{+}$ is difficult as compared to ${\mathrm{NH}}_4^{+}$ because

1. Lone pair of phosphorous is optically inert.

2. Lone pair of phosphorous resides in almost pure p - orbital.

3. Lone pair of phosphorous resides at sp³ orbital.

4. Lone pair of phosphorous resides in almost pure s - orbital.

By heating which of the following, would NO₂ be produced?

1. NaNO₃

2. AgNO₃

3. NH₄NO₃

4. NH₄NO₂