Question:
$E^\circ$ values of $Mg²+/Mg$ is -2.37 V, of $Zn²+/Zn$ is -0.76 V and $Fe²+/Fe$ is -0.44 V. Which of the statements is correct?
$E^\circ$ values of $Mg²+/Mg$ is -2.37 V, of $Zn²+/Zn$ is -0.76 V and $Fe²+/Fe$ is -0.44 V. Which of the statements is correct?
Show Hint
$E/Mg$ is -2.37 V, of $Zn/Zn$ is -0.76 V and $Fe/Fe$ is -0.44 V. Which of the statements is correct?
Updated On: Apr 15, 2026
- Zn will reduce $Fe^{2+}$
- Zn will reduce $Mg^{2+}$
- Mg oxidises Fe
- Zn oxidises Fe
Show Solution
Verified By Collegedunia
The Correct Option is A
Solution and Explanation
Step 1: Concept
A higher negative value of standard reduction potential ($E^{\circ}$) indicates a stronger reducing power.
Step 2: Analysis
The order of $E^{\circ}$ values (reducing power) is: $-2.37 \text{ (Mg)}>-0.76 \text{ (Zn)}>-0.44 \text{ (Fe)}$
Step 3: Conclusion
Mg can reduce both $Zn^{2+}$ and $Fe^{2+}$. Zn can reduce $Fe^{2+}$, but it cannot reduce $Mg^{2+}$. Iron (Fe) can neither reduce Mg nor Zn, but it can oxidise them. Thus, statement (A) is correct.
Final Answer: (A)
A higher negative value of standard reduction potential ($E^{\circ}$) indicates a stronger reducing power.
Step 2: Analysis
The order of $E^{\circ}$ values (reducing power) is: $-2.37 \text{ (Mg)}>-0.76 \text{ (Zn)}>-0.44 \text{ (Fe)}$
Step 3: Conclusion
Mg can reduce both $Zn^{2+}$ and $Fe^{2+}$. Zn can reduce $Fe^{2+}$, but it cannot reduce $Mg^{2+}$. Iron (Fe) can neither reduce Mg nor Zn, but it can oxidise them. Thus, statement (A) is correct.
Final Answer: (A)
Was this answer helpful?
0
0
Top MET Chemistry Questions
- Which of the following product is formed in the reaction $ CH_3MgBr {->[(i)CO_2][(ii)H_2O]} ? $
- Ethyl chloride is converted into diethyl ether by:
- Correct order of reactivity:
- A group of 13 element if added in small amounts to Ge, then the type of semiconductor formed is
- Consider the following statements I. Repulsive forces are significant when the molecules are close together on average. II. Attractive intermolecular forces are important when the molecules are fairly close together but not necessarily touching. III. Attractive forces are ineffective when the molecules are for apart. Select correct statements.
View More Questions
Top MET Electrochemical Cells Questions
- The emf \( E^{\circ} \) of the following cells are:
\( \mathrm{Ag} \mid \mathrm{Ag}^{+} (1\text{ M}) \parallel \mathrm{Cu}^{2+} (1\text{ M}) \mid \mathrm{Cu}; \, E^{\circ} = -0.46 \text{ V} \)
\( \mathrm{Zn} \mid \mathrm{Zn}^{2+} (1\text{ M}) \parallel \mathrm{Cu}^{2+} (1\text{ M}) \mid \mathrm{Cu}; \, E^{\circ} = 1.10 \text{ V} \)
emf of the cell \( \mathrm{Zn} \mid \mathrm{Zn}^{2+} (1\text{ M}) \parallel \mathrm{Ag}^{+} (1\text{ M}) \mid \mathrm{Ag} \) is: - The emf \( E^{\circ} \) of the following cells are:
\( \mathrm{Ag} \mid \mathrm{Ag}^{+} (1\text{ M}) \parallel \mathrm{Cu}^{2+} (1\text{ M}) \mid \mathrm{Cu}; \, E^{\circ} = -0.46 \text{ V} \)
\( \mathrm{Zn} \mid \mathrm{Zn}^{2+} (1\text{ M}) \parallel \mathrm{Cu}^{2+} (1\text{ M}) \mid \mathrm{Cu}; \, E^{\circ} = 1.10 \text{ V} \)
emf of the cell \( \mathrm{Zn} \mid \mathrm{Zn}^{2+} (1\text{ M}) \parallel \mathrm{Ag}^{+} (1\text{ M}) \mid \mathrm{Ag} \) is: - The standard reduction potentials at 298 K for half-cell reactions are given:
\( \mathrm{Zn}^{2+} + 2e^{-} \rightarrow \mathrm{Zn};\ -0.762\,\text{V} \)
\( \mathrm{Cr}^{3+} + 3e^{-} \rightarrow \mathrm{Cr};\ -0.74\,\text{V} \)
\( 2\mathrm{H}^{+} + 2e^{-} \rightarrow \mathrm{H}_{2};\ 0.00\,\text{V} \)
\( \mathrm{Fe}^{3+} + e^{-} \rightleftharpoons \mathrm{Fe}^{2+};\ +0.77\,\text{V} \)
The strongest reducing agent is: - The standard reduction potentials at 298 K for half-cell reactions are given:
\( \mathrm{Zn}^{2+} + 2e^{-} \rightarrow \mathrm{Zn};\ -0.762\,\text{V} \)
\( \mathrm{Cr}^{3+} + 3e^{-} \rightarrow \mathrm{Cr};\ -0.74\,\text{V} \)
\( 2\mathrm{H}^{+} + 2e^{-} \rightarrow \mathrm{H}_{2};\ 0.00\,\text{V} \)
\( \mathrm{Fe}^{3+} + e^{-} \rightleftharpoons \mathrm{Fe}^{2+};\ +0.77\,\text{V} \)
The strongest reducing agent is: - A radioactive substance has a half-life of 60 min. During 3 hours, the fraction of the substance that has decayed is:
View More Questions
Top MET Questions
- A coil of 100 turns and area $2 \times 10^{-2}m^2 $ is pivoted about a vertical diameter in a uniform magnetic field and carries a current of 5A. When the coil is held with its plane in north-south direction, it experiences a couple of 0.33 Nm. When the plane is east-west, the corresponding couple is 0.4 Nm, the value of magnetic induction is [Neglect earth's magnetic field]
- $\int\limits_{0}^{8}| x -5| d x$ is equal to
- Radiation, with wavelength 6561 $?$ falls on a metal surface to produce photoelectrons. The electrons are made to enter a uniform magnetic field of $3 \times 10^{-4} T$. If the radius of the largest circular path followed by the electrons is 10 mm, the work function of the metal is close to :
- In intrinsic semiconductor at room temperature number of electrons and holes are
- Which of the following product is formed in the reaction $ CH_3MgBr {->[(i)CO_2][(ii)H_2O]} ? $
View More Questions