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The standard oxidation potentials, , fo...

The standard oxidation potentials, , for the half reactions are as follows :
`Zn rightarrow Zn^(2+) + 2e^(-)` ,` E^(@) = +0.76V`
`Fe rightarrow Fe^(2+)+ 2e^(-), E^(@) = + 0.41 V`
The EMF for the cell reaction,
`Fe^(2+) + Zn rightarrow Zn^(2+) + Fe`

A

`(-0.35V)`

B

(+0.35V)

C

`(+1.17V)`

D

`(1.17V)`

Text Solution

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The correct Answer is:
To solve the problem, we need to calculate the EMF (Electromotive Force) for the given cell reaction: **Cell Reaction:** \[ \text{Fe}^{2+} + \text{Zn} \rightarrow \text{Zn}^{2+} + \text{Fe} \] **Step 1: Identify the half-reactions and their standard oxidation potentials.** - The half-reactions given are: 1. \( \text{Zn} \rightarrow \text{Zn}^{2+} + 2e^- \) with \( E^\circ = +0.76 \, \text{V} \) (oxidation potential) 2. \( \text{Fe} \rightarrow \text{Fe}^{2+} + 2e^- \) with \( E^\circ = +0.41 \, \text{V} \) (oxidation potential) **Step 2: Convert oxidation potentials to reduction potentials.** - The reduction potential is the negative of the oxidation potential: - For Zinc: \[ E^\circ_{\text{Zn}} = -0.76 \, \text{V} \] - For Iron: \[ E^\circ_{\text{Fe}} = -0.41 \, \text{V} \] **Step 3: Determine which species is oxidized and which is reduced.** - In the reaction, Zn is oxidized (loses electrons) and Fe²⁺ is reduced (gains electrons). - Therefore: - Anode (oxidation): Zn - Cathode (reduction): Fe²⁺ **Step 4: Calculate the EMF of the cell.** - The EMF (E_cell) can be calculated using the formula: \[ E_{\text{cell}} = E^\circ_{\text{cathode}} - E^\circ_{\text{anode}} \] - Substituting the values: \[ E_{\text{cell}} = (-0.41 \, \text{V}) - (-0.76 \, \text{V}) \] \[ E_{\text{cell}} = -0.41 + 0.76 \] \[ E_{\text{cell}} = 0.35 \, \text{V} \] **Final Answer:** The EMF for the cell reaction is \( 0.35 \, \text{V} \). ---

To solve the problem, we need to calculate the EMF (Electromotive Force) for the given cell reaction: **Cell Reaction:** \[ \text{Fe}^{2+} + \text{Zn} \rightarrow \text{Zn}^{2+} + \text{Fe} \] **Step 1: Identify the half-reactions and their standard oxidation potentials.** - The half-reactions given are: 1. \( \text{Zn} \rightarrow \text{Zn}^{2+} + 2e^- \) with \( E^\circ = +0.76 \, \text{V} \) (oxidation potential) ...
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The standard reductino potentials E^(c-) for the half reactinos are as follows : ZnrarrZn^(2+)+2e^(-)" "E^(c-)=+0.76V FerarrFe^(2+)+2e^(-) " "E^(c-)=0.41V The EMF for the cell reaction Fe^(2+)+Znrarr Zn^(2+)+Fe is

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The standard oxidation potential of Zn and Ag in water at 20^(@) C" are: " Zn(s) rarr Azn^(2+) (aq) + 2e^(-) E^(o) = 0.76 V Ag(s) rarr Ag^(+)(aq) +e^(-) E^(o) = - 0.80 V Which one of the following reactions actually takes place?

The standard electrode potential of the half cells are given below : Zn^(2+)+ 2e^(-) rarr Zn(s), E^(o) = - 7.62 V Fe^(2+) + 2e^(-) rarr Fe(s) , E^(o) = -7 .81 V The emf of the cell Fe^(2+) + Zn rarr Zn^(2+) + Fe will be :

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The half cell reactions for rusting of iron are : 2H^(+) + 2e^(-) + (1)/(2)O_(2) rightarrow H_(2)O (l) , E^(@) = +1.23V Fe^(2+) + 2e^(-) rightarrow Fe , E^(@) = -0.44V Delta^(@) ((inKJ) for the reaction is : Fe+2H^(+) + (1)/(2) O_(2)rightarrow Fe^(+2)+ H_(2) O ((l))

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