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प्रश्न
Calculate `"E"_"cell"^circ` of the following galvanic cell:
Mg(s) / Mg2+(1 M) // Ag+ (1 M) / Ag(s) if `"E"_"Mg"^circ` = – 2.37 V and `"E"_"Ag"^circ` = 0.8 V. Write cell reactions involved in the above cell. Also mention if cell reaction is spontaneous or not.
उत्तर
Given: `"E"_"Mg"^circ` = – 2.37 V and `"E"_"Ag"^circ` = 0.8 V
To find: Standard cell potential
Formula: `"E"_"cell"^circ = "E"_"cathode"^circ - "E"_"anode"^circ`
Calculation: `"E"_"cell"^circ = "E"_"cathode"^circ - "E"_"anode"^circ`
`"E"_"cell"^circ = "E"_"Ag"^circ - "E"_"Mg"^circ`
= (0.8 V) - (- 2.37 V) = 3.17 V
The standard cell potential for the reaction is 3.17 V.
Cell reactions:
Electrode reactions are
| At anode: | \[\ce{Mg_{(s)} -> Mg^{2+}_{ (aq)} + 2e-}\] |
| At cathode: | \[\ce{Ag^+_{ (aq)} + e^- -> Ag_{(s)}}\] |
| Overall cell reaction- \[\ce{Mg_{(s)} + 2Ag^+_{ (aq)} -> Mg^{2+}_{ (aq)} + 2Ag_{(s)}}\] | |
Since the standard cell potential is positive, the cell reaction is spontaneous.
संबंधित प्रश्न
Consider the half reactions with standard potentials.
- \[\ce{Ag^{\oplus}_{ (aq)} + e^{\ominus} -> Ag_{(s)}E^\circ = 0.8 V}\]
- \[\ce{I2_{(s)} + 2e^\ominus -> 2I^{\ominus}_{(aq)} E^\circ = 0.53V}\]
- \[\ce{Pb^{2\oplus}_{(aq)} + 2e^{\ominus} -> Pb_{(s)} E^\circ = -0.13 V}\]
- \[\ce{Fe^{2\oplus} + 2e^{\ominus} -> Fe_{(s)} E^\circ = -0.44 V}\]
The strongest oxidising and reducing agents respectively are ______.
Answer the following in one or two sentences.
What is standard cell potential for the reaction
\[\ce{3Ni_{(s)} + 2Al^{3+} (1M) → 3Ni^{2+} (1M) + 2Al(s)}\], if `E_"Ni"^circ` = –0.25 V and `"E"_("Al")^circ` = –1.66 V?
Answer the following in one or two sentences.
Under what conditions the cell potential is called standard cell potential?
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E°Zn = −076V, E°Cr = −0.74V.
Answer the following:
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Calculate \[\ce{E^0_{cell}}\] for the following cell.
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Given: `"E"_("Cr"^(3+)//"Cr")^0` = −0.74 V,
`"E"_("Fe"^(2+)//"Fe")^0` = −0.44 V
Identify the strongest reducing agent from the data given below:
| Element | `"E"^0 ("V")` |
| Al | −1.66 |
| Fe | −0.44 |
| Hg | +0.79 |
| Cu | +0.337 |
What is the standard potential of cell, Ni | Ni2+ (1M) || Cu2+ (1 M) | Cu?
If E°Cu = 0.337 V and E°Ni = - 0.236 V.
The tendency of an electrode to lose electrons is known as ______
The standard potential of the cell in the following reaction is ______.
\[\ce{Cd_{(s)} + Cu^{2+}_{(1M)} -> Cd^{2+}_{(1M)} + Cu_{(s)}}\]
`("E"_("Cd")^circ = - 0.403V, "E"_("Cu")^circ = 0.334V)`
Which element from the following has the highest negative standard reduction potential?
Construct a cell from Ni2+ | Ni and Cu2+ | Cu Cu half cells. Write the cell reaction and calculate `E_("cell")^0`
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Define standard electrode potential.
The standard potential of the electrode Zn2+(0.02M) |Zn(s) is − 0.76 V. Calculate the electrode potential of the zinc electrode.
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Write the four applications of emf series.
