Download App

2. Electrochemistry — Chemistry STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceChemistry2. Electrochemistry1 Mark
MCQ
The reaction at cathode in the cells commonly used in clocks involves.
  • ✓
    reduction of $\mathrm{Mn}$ from $+4 to +3$
  • B
    oxidation of $\mathrm{Mn}$ from $+3 to +4$
  • C
    reduction of $\mathrm{Mn}$ from $+7 to +2$
  • D
    oxidation of $\mathrm{Mn}$ from $+2 to +7$
✓

Answer

Correct option: A.
reduction of $\mathrm{Mn}$ from $+4 to +3$
a
In the cathode reaction manganese $(\mathrm{Mn})$ is reduced from the $+4$ oxidation state to the $+3$ state.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "M.C.Q (1 Marks)" from 2. Electrochemistry→2. Electrochemistry — all question types→Chemistry STD 12 Science question papers→Gujarat Board STD 12 Science question papers→Gujarat Board question paper generator→

Similar questions

 The above reaction completes with the mechanism
→
A certain element forms a solid oxide which when dissolved in water forms an acidic solution, the element is
→
The most common industrial application of chemical effects of electric current is:
→
At $25\,^oC$ , the molar conductivity at infinite dilution for electrolytes $KOH, KCl$ and $BaCl_2$ are $248 \times 10^{-4}, 126 \times 10^{-4}$ and $280 \times 10^{ -4}\,Sm^2\,mol^{-1}$ respectively calculate $\Lambda _m^\infty $ for $Ba(OH)_2$ (in $Sm^2\, mol^{-1}$ )
→
$Zn $ is related to which group
→
The highest magnetic moment is shown by the transition metal ion with which of the following outermost electronic configuration?
→
How many gram of cobalt metal will be deposited when a solution of cobalt $(II)$ chloride is electrolyzed with a current of $10$ amperes for $109$ minutes $(1$ Faraday $= 96,500\, C;$ Atomic mass of  $Co = 59\, u)$
→
The increase in equivalent conductance of an electrolyte solution with dilution is due to the increase in
→
Predict major product of the above reaction is
→
Which statement is correct for product $‘X’$ ?

$\begin{array}{*{20}{c}}
  {O\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,C \equiv CH\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,O\,\,\,} \\ 
  {\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,||\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,||\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,} \\ 
  {Cl - C - C{H_2} - C - C{H_2} - C{H_2} - C - C{H_3}} \\ 
  {|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,} \\ 
  {C{H_2}\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,} \\ 
  {|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,} \\ 
  {C \equiv N\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,} 
\end{array}$ $\xrightarrow[{BaS{O_4}}]{{{H_2}/Pd}}\,'X'$

→