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

1.	Ionisation enthalpy of hydrogen resembles that of alkali metals
2.	Its reactivity is similar to halogens
3.	It resembles both alkali metals and halogens
4.	Loss of an electron from hydrogen atom results in a nucleus of very small size as compared to other atoms or ions. Due to small size it cannot exist free

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.

Which of the following reactions increases production of dihydrogen from synthesis gas?

1. ${\mathrm{CH}}_4\left(\mathrm{g}\right)+{\mathrm{H}}_2\mathrm{O}\left(\mathrm{g}\right)\underset{\mathrm{Ni}}{\overset{1270 \mathrm{K}}{\to }}\mathrm{CO}\left(\mathrm{g}\right)+3{\mathrm{H}}_2\left(\mathrm{g}\right)$

2. $\mathrm{C}\left(\mathrm{s}\right)+{\mathrm{H}}_2\mathrm{O}\left(\mathrm{g}\right)\stackrel{1270 \mathrm{K}}{\to }\mathrm{CO}\left(\mathrm{g}\right)+{\mathrm{H}}_2\left(\mathrm{g}\right)$

3. $\mathrm{CO}\left(\mathrm{g}\right)+{\mathrm{H}}_2\mathrm{O}\left(\mathrm{g}\right)\underset{\mathrm{Catalyst}}{\overset{673 \mathrm{K}}{\to }}{\mathrm{CO}}_2\left(\mathrm{g}\right)+{\mathrm{H}}_2\left(\mathrm{g}\right)$

4. ${\mathrm{C}}_2{\mathrm{H}}_6+2{\mathrm{H}}_2\mathrm{O}\underset{\mathrm{Ni}}{\overset{1270 \mathrm{K}}{\to }}2\mathrm{CO}+5{\mathrm{H}}_2$