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

When sodium peroxide is treated with dilute sulphuric acid, we get _____.

Hydrogen peroxide is obtained by the electrolysis of ______.

1.  water

2.  sulphuric acid

3.  hydrochloric acid

4.  fused sodium peroxide

Which of the following reactions is an example of use of water gas in the synthesis of other compounds?

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

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

3.  ${\mathrm{C}}_{\mathrm{n}}{\mathrm{H}}_{2\mathrm{n}+2}+{\mathrm{nH}}_2\mathrm{O}\left(\mathrm{g}\right)\underset{\mathrm{Ni}}{\overset{1270 \mathrm{K}}{\to }}\mathrm{nCO}+(2\mathrm{n}+1){\mathrm{H}}_2$

4.  $\mathrm{CO}\left(\mathrm{g}\right)+2{\mathrm{H}}_2\left(\mathrm{g}\right)\underset{\mathrm{Catalyst}}{\overset{\mathrm{Cobalt}}{\to }}{\mathrm{CH}}_3\mathrm{OH}\left(\mathrm{l}\right)$

Which of the following ions will cause hardness in water sample?

1. Ca²⁺

2.  Na⁺

3.  Cl^-

4.  K⁺