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महाराष्ट्र राज्य शिक्षण मंडळएचएससी विज्ञान (सामान्य) इयत्ता १२ वी

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

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प्रश्न

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

थोडक्यात 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

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Derive a relation between ΔH and ΔU for a chemical reaction. Draw neat labelled diagram of calomel electrode. Resistance and conductivity of a cell containing 0.001 M KCI solution at 298K are 1500Ω and 1.46x10-4 S.cm-1 respectively.


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(i) less than 2.71 V and
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Which of the following is TRUE for this data?


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Assertion: pure iron when heated in dry air is converted with a layer of rust.

Reason: Rust has the compositionFe3O4.


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


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An electrochemical cell can behave like an electrolytic cell when ______.


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.

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

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