Hydrogen resembles halogens in many respects for which several factors are responsible. Of the following factors which one is most important in this respect?

1.	Its tendency to lose an electron to form a cation.
2.	Its tendency to gain a single electron in its valence shell to attain stable electronic configuration.
3.	Its low negative electron enthalpy value.
4.	Its small size.

H⁺ ions always get associated with other atoms or molecules due to -

Metal hydrides are ionic, covalent or molecular in nature. Among LiH, NaH, KH, RbH, CsH, the correct order of increasing ionic character is

1.  LiH > NaH > CsH > KH > RbH

2.  LiH < NaH < KH < RbH < CsH

3.  RbH > CsH > NaH > KH > LiH

4.  KH < NaH < RbH < LiH < CsH

Which of the following hydrides is electron-precise hydride?

1. B₂H₆

2. NH₃

3. H₂O

4. CH₄

Radioactive elements emit $\mathrm{\alpha }$, $\mathrm{\beta }$ , and $\mathrm{\gamma }$ rays and are characterized by their half-lives. The radioactive isotope of hydrogen is

1. Protium

2. Deuterium 

3. Tritium

4. Hydronium

Consider the reactions

(i) ${\mathrm{H}}_2{\mathrm{O}}_2+2\mathrm{HI}\to {\mathrm{I}}_2+2{\mathrm{H}}_2\mathrm{O}$

(ii) $\mathrm{HOCl}+{\mathrm{H}}_2{\mathrm{O}}_2\to {\mathrm{H}}_3{\mathrm{O}}^{+}+{\mathrm{Cl}}^{-}+{\mathrm{O}}_2$

Which of the following statements is correct about H₂O₂ with reference to these reactions? Hydrogen peroxide is ______.

1.  an oxidising agent in both (i) and (ii)

2.  an oxidisng agent in (i) and reducing agent in (ii)

3.  a reducing agent in (i) and oxidising agent in (ii)

4.  a reducing agent in both (i) and (ii)

The oxide that gives ${\mathrm{H}}_2{\mathrm{O}}_2$ on treatment with dilute ${\mathrm{H}}_2{\mathrm{SO}}_4$ is

1. ${\mathrm{PbO}}_2$

2. ${\mathrm{BaO}}_2.8{\mathrm{H}}_2\mathrm{O}+{\mathrm{O}}_2$

3. ${\mathrm{MnO}}_2$

4. ${\mathrm{TiO}}_2$

Which of the following equations depict the oxidising nature of ${\mathrm{H}}_2{\mathrm{O}}_2$?

1. $2{\mathrm{MnO}}_4^{-}+6{\mathrm{H}}^{+}+5{\mathrm{H}}_2{\mathrm{O}}_2\to 2{\mathrm{Mn}}^{2+}+8{\mathrm{H}}_2\mathrm{O}+5{\mathrm{O}}_2$

2. $2{\mathrm{Fe}}^{3+}+2{\mathrm{H}}^{+}+{\mathrm{H}}_2{\mathrm{O}}_2\to 2{\mathrm{Fe}}^{2+}+2{\mathrm{H}}_2\mathrm{O}+{\mathrm{O}}_2$

3. $2{\mathrm{I}}^{-}+2{\mathrm{H}}^{+}+{\mathrm{H}}_2{\mathrm{O}}_2\to {\mathrm{I}}_2+2{\mathrm{H}}_2\mathrm{O}$

4. ${\mathrm{KIO}}_4+{\mathrm{H}}_2{\mathrm{O}}_2\to {\mathrm{KIO}}_3+{\mathrm{H}}_2\mathrm{O}+{\mathrm{O}}_2$

Which of the following equation depicts reducing nature of ${\mathrm{H}}_2{\mathrm{O}}_2$?

1. $2{\left[\mathrm{Fe}{\left(\mathrm{CN}\right)}_6\right]}^{4-}+2{\mathrm{H}}^{+}+{\mathrm{H}}_2{\mathrm{O}}_2\to 2{\left[\mathrm{Fe}{\left(\mathrm{CN}\right)}_6\right]}^{3-}+2{\mathrm{H}}_2\mathrm{O}$

2.  ${\mathrm{I}}_2+{\mathrm{H}}_2{\mathrm{O}}_2+2{\mathrm{OH}}^{-}\to 2{\mathrm{I}}^{-}+2{\mathrm{H}}_2\mathrm{O}+{\mathrm{O}}_2$

3.  ${\mathrm{Mn}}^{2+}+{\mathrm{H}}_2{\mathrm{O}}_2\to {\mathrm{Mn}}^{4+}+2{\mathrm{OH}}^{-}$

4.  $\mathrm{PbS}+4{\mathrm{H}}_2{\mathrm{O}}_2\to {\mathrm{PbSO}}_4+4{\mathrm{H}}_2\mathrm{O}$

Hydrogen peroxide is-

1. an oxidising agent

2. a reducing agent

3. both an oxidising and a reducing agent

4. neither oxidising nor reducing agent.