Advertisements
Advertisements
प्रश्न
Calculate the voltage of the cell Sn(s) / Sn2+(0.02 M) // Ag+ (0.01 M) / Ag(s) at 25 °C.
Given: `"E"_"Sn"^circ` = - 0.136, `"E"_"Ag"^circ` = 0.800 V
Advertisements
उत्तर
Given: `"E"_"Sn"^circ` = - 0.136, `"E"_"Ag"^circ` = 0.800 V
To find: Voltage of the cell (Ecell)
Formulae:
- `"E"_"cell"^circ = "E"_"cathode"^circ - "E"_"anode"^circ`
- `"E"_"cell" = "E"_"cell"^circ - (0.0592 "V")/"n" log_10 (["Product"])/(["Reactant"])`
Calculation: First we write the cell reaction.
| \[\ce{Sn_{(s)} -> Sn^2+ (0.02 M) + 2e-}\] | (oxidation at anode) |
| [Ag+ (0.01 M) + e– → Ag(s)] × 2 | (reduction at cathode) |
| Overall reaction: \[\ce{Sn_{(s)} + 2Ag^+ (0.01 M) -> Sn^2+ (0.02 M) + 2Ag_{(s)}}\] |
|
Using formula (1),
`"E"_"cell"^circ = "E"_"Ag"^circ - "E"_"Sn"^circ` = 0.800 V - (- 0.136 V) = 0.936 V
Using formula (2),
The cell potential is given by
`"E"_"cell" = "E"_"cell"^circ - (0.0592 "V")/"n" log_10 (["Sn"^(2+)])/(["Ag"^+]^2)`
∴ `"E"_"cell" = 0.936 "V" - (0.0592 "V")/2 log_10 0.02/(0.01)^2`
`= 0.936 "V" - (0.0592 "V")/2 log_10 200`
`= 0.936 "V" - (0.0592 "V")/2 xx 2.301`
Calculation using log table:
0.0592 × 2.303
= Antilog10 [log10 0.0592 + log10 2.303]
= Antilog10 `[bar(2).7723 + 0.3623]`
= Antilog10 `[bar(1).1346]`
= 0.1363
= 0.936 V – `(0.1363 "V")/2` (Using log table)
= 0.936 V – 0.0681 V
= 0.8679 V
The voltage of cell is 0.8679 V.
संबंधित प्रश्न
Choose the most correct option.
The standard potential of the cell in which the following reaction occurs:
H2 (g,1 atm) + Cu2+ (1M) → 2H+ (1M) + Cu(s),
`("E"_"Cu"^circ = 0.34 "V")` is
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.
Write Nernst equation. What part of it represents the correction factor for nonstandard state conditions?
Answer the following:
Calculate emf of the cell:
Zn(s) |Zn2+ (0.2 M)||H+ (1.6 M)| H2(g, 1.8 atm)| Pt at 25 °C.
Answer the following:
Predict whether the following reaction would occur spontaneously under standard state condition.
`"Ca"_(("s")) + "Cd"_(("aq"))^(2+) -> "Ca"_(("aq"))^(2+) + "Cd"_(("s"))`
Answer the following:
Predict whether the following reaction would occur spontaneously under standard state condition.
`2"Br"_(("aq"))^(-) + "Sn"_(("aq"))^(2+) -> "Br"_(2("l")) + "Sn"_(("s"))`
What is cell voltage?
Standard reduction electrode potentials of three metals A, B and C are +0.5 V, −3.0 V and −1.2 V respectively. The reducing power of these metals is ______.
Nernst equation for the following cell reaction at 298 K is:
\[\ce{Mg_{(s)} | Mg^{2+}_{( aq)} || Ag^+_{( aq)} | Ag_{(s)}}\]
Calculate \[\ce{E^0_{cell}}\] for the following cell.
\[\ce{Cr_{(s)} | Cr^{3+}_{( aq)} || Fe^{2+}){( aq)} | Fe_{(s)}}\]
Given: `"E"_("Cr"^(3+)//"Cr")^0` = −0.74 V,
`"E"_("Fe"^(2+)//"Fe")^0` = −0.44 V
The reduction potential of a half-cell consisting of nickel electrode in 0.1 M NiSO4 solution at 25°C is ____________.
(E0 = −0.257 V)
What is the standard emf of the following cell?
\[\ce{Ni_{(s)} | Ni^{2+}_{( aq)} || Au^{3+}_{( aq)} | Au_{(s)}}\]
if \[\ce{E^0_{Ni}}\] = −0.25 V, \[\ce{E^0_{Au}}\] = 1.50 V.
What is the ΔG0 for the following reaction?
\[\ce{Al_{(s)} + Fe^{3+}_{( aq)} -> Al^{3+}_{( aq)} + Fe_{(s)}}\]; \[\ce{E^0_{cell}}\] = +2.43
For the following cell, standard potential of copper electrode is 0.337 V and standard cell potential is 0.463 V.
\[\ce{Cu | Cu^{2+} (1 M) || Ag^+ (1 M) Ag}\]
What is the standard potential of silver electrode?
The standard electrode potential of Zn and Ni are - 0.76 V and - 0.25 V respectively. If the reaction takes place in the cell constructed between these two electrodes is spontaneous. What is the standard emf of the cell?
The tendency of an electrode to lose electrons is known as ______
Answer the following in one or two sentences.
What is the standard cell potential for the reaction?
\[\ce{2Al(s) + 3Ni^{2⊕}(1M) -> 2Al^{3⊕}(1 M) + 3Ni(s)}\]
if \[\ce{E{^{\circ}_{Ni}}}\] = −0.25 V and \[\ce{E{^{\circ}_{Al}}}\] = −1.66 V?
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`
`(E_("Ni")^0 = - 0.236 V and E_("Cu")^0 = + 0.337 V)`
Write net cell reaction.
Write the four applications of emf series.
Standard potential (E°) of
\[\mathrm{Zn_{(aq)}^{+2}+2e^{-}\longrightarrow Zn_{(s)}~is~-0.76~V}\]
What is standard potential of reaction
\[2\mathrm{Zn}_{(\mathrm{s})}\longrightarrow2\mathrm{Zn}_{(\mathrm{aq})}^{+2}+4\mathrm{e}^{-}\] ?
Which from following formulae is used to obtain value of E°cell for a reaction taking place in Dry cell?
