Which of the following is not an example of redox reaction?

1. $\mathrm{CuO}+{\mathrm{H}}_2\to \mathrm{Cu}+{\mathrm{H}}_2\mathrm{O}$

2. ${\mathrm{Fe}}_2{\mathrm{O}}_3+3\mathrm{CO}\to 2\mathrm{Fe}+3{\mathrm{CO}}_2$

3. $2\mathrm{K}+{\mathrm{F}}_2\to 2\mathrm{KF}$

4. ${\mathrm{BaCl}}_2+{\mathrm{H}}_2{\mathrm{SO}}_4\to {\mathrm{BaSO}}_4+2\mathrm{HCl}$

Using the standard electrode potentials of the redox couples given below, which of the following is the strongest oxidizing agent?

${\mathrm{E}}^{⊝} \mathrm{values}: {\mathrm{Fe}}^{3+}/{\mathrm{Fe}}^{2+}=+0.\mathrm{77\; V}$ 
${\mathrm{I}}_2\left(\mathrm{s}\right)/{\mathrm{I}}^{-}=+0.54 V$
${\mathrm{Cu}}^{2+}/\mathrm{Cu}=+0.\mathrm{34\; V}$
${\mathrm{Ag}}^{+}/\mathrm{Ag}=0.\mathrm{80\; V}$

1. Fe³⁺
2. I₂(s)
3. Cu²⁺
4. Ag⁺

${\mathrm{E}}^{\Theta }$ values of some redox couples are given below. On the basis of these values choose the correct option.

${\mathrm{E}}^{\mathrm{\Theta }} \mathrm{values}: {\mathrm{Br}}_2/{\mathrm{Br}}^{-}=+1.90$
${\mathrm{Ag}}^{+}/\mathrm{Ag}\left(\mathrm{s}\right)=+0.80$
${\mathrm{Cu}}^{2+}/\mathrm{Cu}\left(\mathrm{s}\right)=+0.34;$
${\mathrm{I}}_2\left(\mathrm{s}\right)/{\mathrm{I}}^{-}=+0.54$

Using the standard electrode potential, find out the pair between which redox reaction is not feasible.

${\mathrm{E}}^{⊝} \mathrm{values}: {\mathrm{Fe}}^{3+}/{\mathrm{Fe}}^{2+}=+0.77; {\mathrm{I}}_2/{\mathrm{I}}^{-}=+0.54;$
${\mathrm{Cu}}^{2+}/\mathrm{Cu}=+0.34; {\mathrm{Ag}}^{+}/\mathrm{Ag}=+0.80 \mathrm{V}$

1. Fe³⁺ and I^-

2. Ag⁺ and Cu

3. Fe³⁺ and Cu

4. Ag and Fe³⁺

In the reactions given below, thiosulphate reacts differently with iodine than with bromine.

$2{\mathrm{S}}_2{\mathrm{O}}_3^{2-}+{\mathrm{I}}_2\to {\mathrm{S}}_4{\mathrm{O}}_6^{2-}+2{\mathrm{I}}^{-}$

${\mathrm{S}}_2{\mathrm{O}}_3^{2-}+2{\mathrm{Br}}_2+5{\mathrm{H}}_2\mathrm{O}\to 2{\mathrm{SO}}_4^{2-}+2{\mathrm{Br}}^{-}+10{\mathrm{H}}^{+}$

Choose the statements among the following that best describe the above dual behaviour of thiosulphate.

The incorrect statement regarding the rule to find the oxidation number among the following is-

In which of the following compounds, an element exhibits two different oxidation state?

1. ${\mathrm{NH}}_2\mathrm{OH}$

2. ${\mathrm{NH}}_4{\mathrm{NO}}_3$

3. ${\mathrm{N}}_2{\mathrm{H}}_4$

4. ${\mathrm{N}}_3\mathrm{H}$

Which of the following arrangements represents the increasing oxidation number of the central atom?

1. ${\mathrm{CrO}}_2^{-},$ ${\mathrm{ClO}}_3^{-},$ ${\mathrm{CrO}}_4^{2-},$ ${\mathrm{MnO}}_4^{-}$

2. ${\mathrm{ClO}}_3^{-},$ ${\mathrm{CrO}}_4^{2-},$ ${\mathrm{MnO}}_4^{-},$ ${\mathrm{CrO}}_2^{-}$

3. ${\mathrm{CrO}}_2^{-},$ ${\mathrm{ClO}}_3^{-},$ ${\mathrm{MnO}}_4^{-},$ ${\mathrm{CrO}}_4^{2-}$

4. ${\mathrm{CrO}}_4^{2-},$ ${\mathrm{MnO}}_4^{-},$ ${\mathrm{CrO}}_2^{-},$ ${\mathrm{ClO}}_3^{-}$

Match Column I with Column II for the oxidation states of the central atoms.

Codes

Match the items in Column I with relevant items in Column II.

Codes