What is the number of moles of K₂Cr₂O₇ required to oxidise 1 mole of ferrous oxalate in an acidic medium?

1.	\(1 \over 2\)	2.	\(1 \over 3\)
3.	\(1\over 6\)	4.	2

The oxidation number of sulfur in \(H_2SO_4\)​ is +6, and in \(H_2S_2O_8\)​, it is also +6. When \(H_2SO_4\)​ is converted into \(H_2S_2O_8\)​, what type of process occurs during this conversion?

1. Oxidation 

2. Reduction 

3. Neither oxidation nor reduction 

4. Oxidation as well as reduction 

Consider the given reaction:
\(\mathrm{Al}+\mathrm{Fe}_3 \mathrm{O}_4 \rightarrow \mathrm{Al}_2 \mathrm{O}_3+\mathrm{Fe}\)

What is the total number of electrons transferred in the given reaction?
1. 6
2. 8
3. 8/3
4. 24

The correct statement about the electrolysis of an aqueous solution of ${\mathrm{AgNO}}_3$ with Ag electrode is:

The set of metals/metal ion that can show disproportionation reaction is:

From the following, identify the reaction having the top position in the EMF series (standard reduction potential) according to their electrode potential at 298 K.

In an electrochemical cell, the half-cell reactions with their respective oxidation potentials are:

\(\begin{aligned} &C u(s) \rightarrow C u^{2+}+2 e^{-} ; E^{\circ}=-0.34 V \\ &N i (s) \rightarrow N i^{2+}+2 e^{-} ; E^{\circ}=+0.25 V \end{aligned} \)

The reaction, among the following, that will be spontaneous is:

1. 2Ni(s) + Cu²⁺(aq) → Ni²⁺(aq) + 2Cu(s)

2. Ni²⁺(aq) + Cu(s) → Ni(s) + Cu²⁺(aq)

3. 2Cu(s) + Ni²⁺(aq) → 3Cu⁺(aq) + Ni(s)

4. Ni(s) + Cu²⁺(aq) → Ni²⁺(aq) + Cu(s)