CBSE Questions for Class 11 Medical Chemistry Redox Reactions Quiz 14 - MCQExams.com

Select the correct statement.
1769603_a6e4f05adb68414a990e34303dd7f6c3.png
  • Oxidation number of $$C$$ in $$RCHO$$ increases and that of $$R'CHO$$ decreases.
  • Oxidation number of $$C$$ in $$RCHO$$ decreases and that of $$RHO$$ increases.
  • Oxidation number of $$C$$ remains unchanged in both but that of oxygen is affected.
  • In $$CH_3CHO$$ and $$C_6H_5CHO,$$ the former can act as $$RCHO$$ (hydride donor).
$$E^o_{Cell}$$ for some half-cell reactions are given below. On the basis of these mark the correct answers.

(a) $$H^- (aq) + e^- \rightarrow \frac{1}{2} H_2 (g); E^o_{Cell} = 1.23V$$

(b) $$2H_2O(l) \rightarrow O_2(g) + 4H^- (aq) + 4e^- ; E^o_{Cell} = 1.23V$$

(c) $$2SO^{2-}_4(aq) \rightarrow S_2O^{2-}_8(aq) + 2e^-; E^o_{Cell} = 1.96V$$
  • In dilute sulphuric acid solution, hydrogen will be reduced at cathode.
  • In concentrated sulphuric acid solution, water will be oxidised at anode.
  • In dilute sulphuric acid solution, water will be oxidised at anode.
  • In concentrated sulphuric acid solution, $$SO^{2-}_4$$ ion will be oxidized to tetrathionate ion at anode.
Standard electrode potential data are useful for understanding the suitability of an oxidant in a redox titration. Some half cell reactions and their standard potentials are given below:  $$MnO^{-}_4(aq)+8H^{+}(aq)+6e^{-} \longrightarrow $$  $$ \mathrm{Mn}^{2+}(a q)+4 \mathrm{H}_{2} \mathrm{O}(l) \mathrm{E}^{\circ}=1.51 \mathrm{V} $$
$$ \mathrm{Cr}_{2} \mathrm{O}_{7}^{2-}(a q)+14 \mathrm{H}^{+}(a q)+6 e^{-} \longrightarrow $$ $$ 2 \mathrm{Cr}^{3+}(a q)+7 \mathrm{H}_{2} \mathrm{O}(l) ; \mathrm{E}^{\circ}=1 \cdot 38 \mathrm{V} $$
$$ \mathrm{Fe}^{3+}(a q)+e^{-} \longrightarrow \mathrm{Fe}^{2+}(a q) ; \mathrm{E}^{\circ}=0.77 \mathrm{V} $$
$$ \mathrm{Cl}_{2}(g)+2 e^{-} \rightarrow 2 \mathrm{Cl}^{-}(a q) ; \mathrm{E}^{\circ}=1 \cdot 40 \mathrm{V} $$

Identify the only incorrect statement regarding the quantitative estimation of aqueous
$$ \mathrm{Fe}\left(\mathrm{NO}_{3}\right)_{2} $$
  • $$ \mathrm{MnO}_{4}^{-} $$ can be used in aqueous $$HCl$$
  • $$ \mathrm{Cr}_{2} \mathrm{O}_{7}^{2-} $$ can be used in aqueous $$HCl$$
  • $$ \mathrm{MnO}_{4}^{-} $$ can be used in aqueous $$ \mathrm{H}_{2} \mathrm{SO}_{4} $$
  • $$ \mathrm{Cr}_{2} \mathrm{O}_{7}^{2-} $$ can be used in aqueous $$ \mathrm{H}_{2} \mathrm{SO}_{4} $$
Oxidation number of carbon in $$H_2CO_3$$ is
  • +1
  • +2
  • +3
  • +4
0:0:1


Answered Not Answered Not Visited Correct : 0 Incorrect : 0

Practice Class 11 Medical Chemistry Quiz Questions and Answers