HARD
Earn 100

The half equation for a redox reaction represents an equilibrium between two sides of an equation such as:
Cu2+ (aq) + 2e- ---> Cu (s); Eo= +0.34 v

How will the value of Eo change if the concentration of Cu2+ increases?

Important Questions on Redox Reactions

MEDIUM
Among the following, which is the strongest oxidizing agent?
EASY
The electrode potential of M2+/M of 3 d-series elements shows positive value for?
EASY
Hypophosphorus acid is a good reducing agent because
HARD

An aqueous solution of nickel (II) sulphate was electrolyzed using nickel electrodes. Observe the diagram and answer the question that follows:

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  • What do you observe at the cathode and anode respectively?
MEDIUM
The amount of Ag (atomic mass = 108) deposited at the cathode when a current of 0.5 amp is passed through a solution of AgNO3 for 1 hour is closest to
HARD

An aqueous solution of nickel (II) sulphate was electrolyzed using nickel electrodes. Observe the diagram and answer the question that follows:

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  • Name the cation that remains as a spectator ion in the solution.
MEDIUM
An iron wire is immersed in a solution containing ZnSO4 and NiSO4. When the concentration of each salt is 1M, predict which of the following reaction is likely to proceed.
Given EoZn+2/Zn=-0.76 V
EoFe+2/Fe=-0.44 V
and Eo(Ni+2/Ni)=-0.25 V
HARD

An aqueous solution of nickel (II) sulphate was electrolyzed using nickel electrodes. Observe the diagram and answer the question that follows:

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  • Which equation for the reaction at the anode is correct?
MEDIUM
What is the standard potential of cell NiNi2+1MCu2+1M|Cu If EoCu+2|Cu=0·337 V and EoNi+2|Ni=-0·236 V
EASY

In the following resonance structures, the curved arrow indicates that electrons are shifted from

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MEDIUM
The hydrogen electrode is dipped in a solution of pH=3 at 25°C, the potential of the cell would be (the value of 2.303RTF=0.059V)
EASY
The order of reactivity of K, Mg, Au and Zn with water is
EASY

The electrode potential, E°, for the reduction of MnO4- to Mn2+ in acidic medium is +1.51
V. Which of the following metal(s) will be oxidised? The reduction reactions and standard electrode potentials for Zn2+,Ag+ and Au+Au+ are given as

Zn2+(aq)+2eZn(s),E°=-0.762 V

Ag+(aq)+eAg(s),E°=+0.80 V

Au+(aq)+eAu(s),E°+1.69 V

EASY
Which of the following transformations can be carried out by using HI as a reducing agent, under acidic conditions?

[Given : I2s2I- Eo=0.54 V ]

(i) Cu+Cus  Eo=0.52 V

(ii) Cr3+Cr2+  Eo=-0.41 V

(iii) Fe3+Fe2+  Eo =0.77 V

(iv) Fe2+Fes  Eo=-0.44 V
EASY
Which of the following metals will precipitate copper from copper sulphate solution?
EASY
Predict reaction of 1 N sulphuric acid with the following metals: (i) Copper (ii) lead (iii) iron
Given : ECu2+,Cu=+0.34 volt ; EPb2+,Pb= 0.13 volt ; EFe2+,Fe= 0.44 volt
MEDIUM
Two half cells are Al3+aq/Al and Mg2+(aq)/Mg
The reduction potentials these half cells are 1.66 V and 2.36 V respectively. Calculate the cell potential. Write the cell reaction also.
EASY
Can a solution of 1 M ZnSO4 be stored in a vessel made of copper? Given that
EZn,Zn2+=0.76volt and ECu2+,Cu=0.34volt
EASY
Is it safe to stir 1 M AgNO3 solution with a copper spoon? Given: EAg+,Ag=0.80volt and ECu,Cu2+=0.34volt. Explain.
EASY
If ϕ denotes reduction potential, then which is true?