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Redox Reactions

Long Answer Type

61.

Show that oxidation cannot occur without reduction.
Or
Show that oxidation and reduction go side by side.

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62. In the following reactions:

space space left parenthesis straight i right parenthesis space straight H subscript 2 straight O space plus space 2 FeCl subscript 3 space space space space space rightwards arrow space space space space 2 FeCl subscript 2 space plus space 2 HCl space plus space straight S space space left parenthesis ii right parenthesis space 2 Al space plus space Fe subscript 2 straight O subscript 3 space space rightwards arrow space space space Al subscript 2 straight O subscript 3 space plus space 2 Fe

which is oxidised to what and which is reduced to what? Also, mention the oxidising and reducing agent.

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Short Answer Type

63.

Identify the oxidant and the reductant in the following reactions:
$left parenthesis straight i right parenthesis space Zn left parenthesis straight s right parenthesis space plus space 1 half straight O subscript 2 left parenthesis straight g right parenthesis space space rightwards arrow space space ZnO left parenthesis straight s right parenthesis left parenthesis ii right parenthesis space Zn left parenthesis straight s right parenthesis space plus space 2 straight H to the power of plus left parenthesis aq right parenthesis space space rightwards arrow space space Zn to the power of 2 plus end exponent left parenthesis aq right parenthesis space plus space straight H subscript 2 left parenthesis straight g right parenthesis$

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64. In the reactions given below, identify the species undergoing oxidation and reduction:

$left parenthesis straight i right parenthesis space straight H subscript 2 straight S left parenthesis straight g right parenthesis space plus space Cl subscript 2 left parenthesis straight g right parenthesis space space rightwards arrow space space space 2 HCl space left parenthesis straight g right parenthesis space plus space space straight S left parenthesis straight s right parenthesis left parenthesis ii right parenthesis space 3 Fe subscript 3 straight O subscript 4 left parenthesis straight s right parenthesis space plus space 8 Al space left parenthesis straight s right parenthesis space rightwards arrow space space space 9 space Fe left parenthesis straight s right parenthesis space plus space 4 Al subscript 2 straight O subscript 3 left parenthesis straight s right parenthesis left parenthesis iii right parenthesis space 2 Na left parenthesis straight s right parenthesis space plus space straight H subscript 2 left parenthesis straight g right parenthesis space rightwards arrow space space 2 NaH left parenthesis straight s right parenthesis$

(i) H₂S is oxidised because a more electronegative element, chlorine is added to hydrogen or a more electropositive hydrogen has been removed from S and chlorine is reduced because of the addition of hydrogen to it.

(ii) Aluminium is oxidised due to the addition of oxygen to it and ferrous ferric oxide (Fe₃O₄) is reduced due to the removal of oxygen from it.

(iii) Sodium is oxidised while hydrogen is reduced.

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65. Using Stock notation, represent the following compounds : HAuCl₄, Tl₂O,FeO, Fe₂O₃, CuI, CuO, MnO and MnO₂?

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66.

How will you classify the redox reactions?

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Long Answer Type

67.

What are the changes which take place when a redox reaction is carried in a beaker? Explain with the help of a suitable example.
Or
Explain the redox reaction

$Zn space plus space CuSO subscript 4 space space rightwards arrow space space ZnSO subscript 4 space plus space Cu$
occurring in a beaker.

151 Views

68.

What do you mean by redox reactions in aqueous solutions? Give examples.

167 Views

Short Answer Type

69.

Write the half reactions for each of the following redox reactions:
$left parenthesis straight a right parenthesis space 2 Fe to the power of 3 plus end exponent left parenthesis aq right parenthesis space plus space 2 straight I to the power of minus left parenthesis aq right parenthesis space space rightwards arrow space space straight I subscript 2 left parenthesis straight s right parenthesis space plus space 2 Fe to the power of 2 plus end exponent left parenthesis aq right parenthesis left parenthesis straight b right parenthesis space Sn to the power of 2 plus end exponent left parenthesis aq right parenthesis space plus space 2 Hg to the power of 2 plus end exponent left parenthesis aq right parenthesis space rightwards arrow space space Sn to the power of 4 plus end exponent left parenthesis aq right parenthesis space plus space 2 straight H to the power of plus left parenthesis aq right parenthesis$

90 Views

Long Answer Type

70. In the following reactions:

1. space 2 Na left parenthesis straight s right parenthesis space plus space Cl subscript 2 left parenthesis straight g right parenthesis space space space rightwards arrow space space space 2 NaCl left parenthesis straight s right parenthesis 2. space Mg left parenthesis straight s right parenthesis space plus space Cl subscript 2 left parenthesis straight g right parenthesis space space rightwards arrow space space MgCl subscript 2 left parenthesis straight s right parenthesis 3. space Zn left parenthesis straight s right parenthesis space plus space 2 straight H to the power of plus left parenthesis aq right parenthesis space space rightwards arrow space space Zn to the power of 2 plus end exponent left parenthesis aq right parenthesis space plus space straight H subscript 2 left parenthesis straight g right parenthesis

Mention:
(i) Which reactant is oxidised? To what?
(ii) Which reactant is an oxidising agent?
(iii) Which reactant is reduced?
(iv) Which reactant is reducing agent?

102 Views