Download App

2. Electrochemistry — Chemistry STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceChemistry2. Electrochemistry1 Mark
MCQ
Identify the reaction from following having top position in $EMF$ series (Std. red. potential) according to their electrode potential at $298 \;K$.
  • A
    $K ^{+}+1 e ^{-} \rightarrow K _{( s )}$
  • B
    $Mg ^{2+}+2 e ^{-} \rightarrow Mg _{( s )}$
  • C
    $Fe ^{2+}+2 e ^{-} \rightarrow Fe _{( s )}$
  • ✓
    $Au ^{3+}+3 e ^{-} \rightarrow Au _{( s )}$
✓

Answer

Correct option: D.
$Au ^{3+}+3 e ^{-} \rightarrow Au _{( s )}$
d
$\begin{array}{ll}A u^{3+}+3 e^{-} \rightarrow A u(s) & E^{0}=1.40 \vee \\ F e^{2+}+2 e^{-} \rightarrow F e(s) & E^{0}=-0.44 v \\ M g^{2+}+2 e^{-} \rightarrow M g(s) & E^{0}=-2.36 v \\ K^{+}+1 e^{-} \rightarrow K(s) & E^{0}=-2.93 V\end{array}$

As per electrochemical series, $Au ^{3+}$ occupies. the top position.

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

In the reaction, the compound $C$ is

${{C}_{6}}{{H}_{5}}OH\xrightarrow{NaOH}(A)$  $\mathop {\xrightarrow{{\;C{O_2}\;\;\;\;\;\;\;\;\;\;\;\;}}}\limits_{140\,^oC,\;(4 - 7\,)} (B)$   $\xrightarrow{{HCl}}(C),$

→
The major product $'P'$ formed in this reaction
→
Which of the following statements is right
→
A  $Pt$  complex of  $NH_3$  and $Cl$  produces four ions per molecule in the aq. solution is
→
Thomas slag is
→
Identify the principal organic product of the following reaction.
→
Relationship between products $(Q)$ and $(S)$ is

$\mathrm{CH}_{3}-\mathrm{CH}=\mathrm{CH}_{2}$ $\xrightarrow[{{\text{H}}_{2}}{{\text{O}}_{2}},\bar{O}\text{H}]{\text{B}{{\text{H}}_{3}},\text{THF}}(P)$ $\xrightarrow[\text{C}{{\text{H}}_{2}}\text{C}{{\text{l}}_{2}}]{\text{ Pyridinium Chloro Chromate }(\text{PCC})}$ $(Q)$

$\mathrm{CH}_{3}-\mathrm{CH}=\mathrm{CH}_{2}$ $\xrightarrow[NaB{{H}_{4}}\,,\,H{{O}^{\Theta }}]{Hg\,{{(OAc)}_{2}}\,,\,{{H}_{2}}O}(R)$ $\xrightarrow[\text{C}{{\text{H}}_{2}}\text{C}{{\text{l}}_{2}}]{\text{ Pyridinium Chloro Chromate }(\text{PCC})}$ $(S)$

→
A $C_8H_{10}$ hydrocarbon is nitrated by $HNO_3$ and sulphuric acid. Two, and only two, $C_8H_9NO_2$ isomers are obtained, Which of the following fits this evidence ?
→
Calculate $E_{cell}$ of the reaction ............ $\mathrm{V}$

$Mg\left( s \right) + \mathop {2A{g^ + }}\limits_{(0.0001\,M)}  \to \mathop {M{g^{ + 2}}}\limits_{\left( {0.100\,M} \right)}  + 2Ag\left( s \right)$

If $E_{cell}^o = 3.17\,V$

→
Iron displaces copper from its salt solution, because
→