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How Many Faradays of Electricity Are Required to Produce 6 G of Mg from Mgcl2? - Chemistry

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प्रश्न

How many faradays of electricity are required to produce 6 g of Mg from MgCl2?

संक्षेप में उत्तर
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उत्तर

Mg2+ + 2e- → Mg(s)   

1 mole Mg2+ equals 2 mole e- for electrosis

1 mole Mg required 2 Faraday electricity

 rquired 2 faraday electricity

6g Mg will require = `(2 xx 6)/24`

= 0.5 F

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2018-2019 (March) Set 1

संबंधित प्रश्न

What happens if external potential applied becomes greater than E°cell of electrochemical cell?


Arrange the following metals in the order in which they displace each other from the solution of their salts.

\[\ce{Al, Cu, Fe, Mg}\] and \[\ce{Zn}\]


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`Zn|Zn^(2+)(1M)||H^+(1M)|H_(2(g,1atm))|Pt`


Write cathode and anode reaction in a fuel cell.


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Define the following term:

Fuel cell


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(i) less than 2.71 V and
(ii) greater than 2.71 V


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What is the SI unit tor electrochemical equivalent?


How many faradays of electricity are required for the following reaction to occur

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Consider the change in the oxidation state of Bromine corresponding to different emf values as shown in the expression below:

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Cell equation: \[\ce{A + 2B^- -> A^{2+} + 2B}\]

\[\ce{A^{2+} + 2e^- -> A}\] E0 = +0.34 V and log10 k = 15.6 at 300 K for cell reactions find E0 for \[\ce{B^+ + e^- -> B}\]


A gas X at 1 atm is bubbled through a solution containing a mixture of 1 MY and 1 MZ at 25°C. If the reduction potential of Z > Y > X, then ______.


Describe the construction of Daniel cell. Write the cell reaction.


Why is anode in galvanic cell considered to be negative and cathode positive electrode?


Is it possible to store copper sulphate in an iron vessel for a long time?

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Given: \[\ce{E^0_{{Fe^{2+}|Fe}}}\] = −0.44 V


Write a note on sacrificial protection.


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Which of the following statement is not correct about an inert electrode in a cell?


Use the data given in below find out the most stable ion in its reduced form.

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Use the data given in below find out the most stable oxidised species.

`E^0 (Cr_2O_1^(2-))/(Cr_(3+))` = 1.33 V   `E^0 (Cl_2)/(Cl^-)` = 1.36 V

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The quantity of charge required to obtain one mole of aluminium from Al2O3 is ______.


`E_(cell)^Θ` for some half cell reactions are given below. On the basis of these mark the correct answer.

(a) \[\ce{H^{+} (aq) + e^{-} -> 1/2 H_2 (g); E^Θ_{cell} = 0.00V}\]

(b) \[\ce{2H2O (1) -> O2 (g) + 4H^{+} (aq) + 4e^{-}; E^Θ_{cell} = 1.23V}\]

(c) \[\ce{2SO^{2-}_{4} (aq) -> S2O^{2-}_{8} (aq) + 2e^{-}; E^Θ_{cell} = 1.96V}\]

(i) In dilute sulphuric acid solution, hydrogen will be reduced at cathode.

(ii) In concentrated sulphuric acid solution, water will be oxidised at anode.

(iii) In dilute sulphuric acid solution, water will be oxidised at anode.

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(i) 1.1 = `K_c`

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Column I Column II
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Oxidation-reduction reactions are commonly known as redox reactions. They involve transfer of electrons from one species to another. In a spontaneous reaction, energy is released which can be used to do useful work. The reaction is split into two half-reactions. Two different containers are used and a wire is used to drive the electrons from one side to the other and a Voltaic/Galvanic cell is created. It is an electrochemical cell that uses spontaneous redox reactions to generate electricity. A salt bridge also connects to the half-cells. The reading of the voltmeter gives the cell voltage or cell potential or electromotive force. If \[\ce{E^0_{cell}}\] is positive the reaction is spontaneous and if it is negative the reaction is non-spontaneous and is referred to as electrolytic cell. Electrolysis refers to the decomposition of a substance by an electric current. One mole of electric charge when passed through a cell will discharge half a mole of a divalent metal ion such as Cu2+. This was first formulated by Faraday in the form of laws of electrolysis.
The conductance of material is the property of materials due to which a material allows the flow of ions through itself and thus conducts electricity. Conductivity is represented by k and it depends upon nature and concentration of electrolyte, temperature, etc. A more common term molar conductivity of a solution at a given concentration is conductance of the volume of solution containing one mole of electrolyte kept between two electrodes with the unit area of cross-section and distance of unit length. Limiting molar conductivity of weak electrolytes cannot be obtained graphically.

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  3. When does electrochemical cell behaves like an electrolytic cell?  (1)
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    (ii) Why does conductivity of a solution decreases with dilution?  (1)
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Can we construct an electrochemical cell with two half-cells composed of ZnSO4 solution and zinc electrodes? Explain your answer.


Explain why the anode is of negative polarity in a galvanic cell.


What is an electrochemical cell? What does it consist of?


What are electrochemical reactions?


Explain the types of electrochemical cells.


State the term for the following:

Two metal plates or wires through which the current enters and leaves the electrolytic cell.


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