Identify the reaction from following having top position in EMF s…

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→CBSE Board STD 12 Science question papers→CBSE Board question paper generator→

Similar questions

$\underset{(A)}{\mathop{\begin{matrix}
\,\,\,\,\,Ph\,\,\,\,C{{H}_{3}} \\
|\,\,\,\,\,\,\,\,\,\,|\,\, \\
Ph-C-C-C{{H}_{3}} \\
|\,\,\,\,\,\,\,\,\,\,|\,\,\, \\
\,OH\,\,\,OH \\
\end{matrix}}}\,+\underset{(B)}{\mathop{\begin{matrix}
\,\,\,\,Ph\,\,\,Et \\
\,\,|\,\,\,\,\,\,\,\,\,| \\
Ph-C-C-Et \\
\,\,|\,\,\,\,\,\,\,\,\,| \\
\,\,\,\,\,OH\,\,OH \\
\end{matrix}}}\,\xrightarrow{{{H}_{2}}S{{O}_{4}}}$

$(p)$ $\begin{matrix}
Ph\,\,\,\,\,O\, \\
|\,\,\,\,\,\,\,\,||\,\, \\
Ph-C-C-C{{H}_{3}} \\
|\,\,\,\,\,\,\,\,\,\,\,\, \\
C{{H}_{3}}\,\,\,\,\,\,\,\, \\
\end{matrix}$ $(q)$ $\begin{matrix}
\,Ph\,\,\,\,\,O\, \\
\,\,|\,\,\,\,\,\,\,\,|| \\
Ph-C-C-Et \\
|\,\,\,\,\,\,\,\,\,\, \\
Et\,\,\,\,\,\,\,\,\,\, \\
\end{matrix}$

$(r)$ $\begin{matrix}
\,Ph\,\,\,\,\,O\, \\
|\,\,\,\,\,\,\,\,\,\,||\, \\
Ph-C-C-C{{H}_{3}} \\
|\,\,\,\,\,\,\,\,\,\,\,\,\,\, \\
Et\,\,\,\,\,\,\,\,\,\,\,\,\, \\
\end{matrix}$ $(s)$ $\begin{matrix}
\,\,\,Ph\,\,\,\,\,O\, \\
\,\,|\,\,\,\,\,\,\,\,|| \\
Ph-C-C-Et \\
|\,\,\,\,\,\,\,\,\,\, \\
C{{H}_{3}}\,\,\,\, \\
\end{matrix}$

When $(A)$ and $(B)$ reacts with $H_2SO_4$ products obtained are

→

Match List$-I$ with List$-II$

	List$-I$		List$-II$
$(a)$	Sucrose	$(i)$	$\beta$ -D-Galactose and $\beta$ -D-Glucose
$(b)$	Lactose	$(ii)$	$\alpha$ -D-Glucose and $\beta$ -D-Fructose
$(c)$	Maltose	$(iii)$	$\alpha$ -D-Glucose and $\alpha$ -D-Glucose