मराठी
कर्नाटक बोर्ड पी.यू.सी.पीयूसी विज्ञान इयत्ता ११

Consider the reactions: 2SX2OX3X(2−)(aq)+lX2(S)⟶SX4OX6X(2−)(aq)+2lX−(aq) SX2OX3X(2−)(aq)+2BrX2(l)+5HX2O(l)⟶2SOX4X2−(aq)+4BrX−(aq)+10HX+(aq) Why does the same reductant, thiosulphate react - Chemistry

Advertisements
Advertisements

प्रश्न

Consider the reactions:

\[\ce{2S_2O_3^{(2-)}(aq) + l_2(S) -> S_4O_6^{(2-)}(aq) + 2l-(aq)}\]

\[\ce{S_2O_3^{(2-)}(aq) + 2Br_2(l) + 5H_2O(l) -> 2SO_4^{2-} (aq) + 4Br-(aq) + 10H+ (aq)}\]

Why does the same reductant, thiosulphate react differently with iodine and bromine?

संख्यात्मक

उत्तर

The average oxidation number (O.N.) of `"S"_2"O"_3^(2-)` in is +2. Being a stronger oxidising agent than I2, Br2 oxidises `"S"_2"O"_3^(2-)` to `"SO"_4^(2-)`, in which the O.N. of S is +6. However, I2 is a weak oxidising agent. Therefore, it oxidises `"S"_2"O"_3^(2-)` to `"S"_4"O"_6^(2-)`, in which the average O.N. of S is only +2.5. As a result, `"S"_2"O"_3^(2-)` reacts differently with iodine and bromine.

shaalaa.com
Oxidation Number - Types of Redox Reactions
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 8: Redox Reactions - EXERCISES [पृष्ठ २८१]

APPEARS IN

एनसीईआरटी Chemistry - Part 1 and 2 [English] Class 11
पाठ 8 Redox Reactions
EXERCISES | Q 8.14 | पृष्ठ २८१

संबंधित प्रश्‍न

Justify that the following reaction is redox reaction:

\[\ce{4BCl3(g) + 3LiAlH4(s) → 2B2H6(g) + 3LiCl(s) + 3 AlCl3(s)}\]


Suggest a list of the substances where carbon can exhibit oxidation states from –4 to +4 and nitrogen from –3 to +5.


While sulphur dioxide and hydrogen peroxide can act as oxidising as well as reducing agents in their reactions, ozone and nitric acid act only as oxidants. Why?


Identify the substance oxidised, reduced, oxidising agent and reducing agent for the following reaction:

\[\ce{2AgBr (s) + C6H6O2(aq) → 2Ag(s) + 2HBr (aq) + C6H4O2(aq)}\]


Identify the substance oxidised, reduced, oxidising agent and reducing agent for the following reaction:

\[\ce{HCHO(l) + 2[Ag (NH3)2]+(aq) + 3OH–(aq) → 2Ag(s) + HCOO–(aq) + 4NH3(aq) + 2H2O(l)}\]


Identify the substance oxidised, reduced, oxidising agent and reducing agent for the following reaction:

\[\ce{HCHO (l) + 2Cu^{2+}(aq) + 5 OH–(aq) → Cu2O(s) + HCOO–(aq) + 3H2O(l)}\]


Why does the following reaction occur?

\[\ce{XeO^{4-}_6 (aq) + 2F- (aq) + 6H+ (aq) -> XeO3(g) + F_2(g) + 3H_2O(l)}\]

What conclusion about the compound Na4XeO6 (of which `"XeO"_6^(4+)` is a part) can be drawn from the reaction.


What sorts of informations can you draw from the following reaction ?

\[\ce{{(CN)}_{2(g)} + 2OH-_{(aq)} -> CN-_{(aq)} + CNO-_{(aq)} + H_2O_{(l)}}\]


Refer to the periodic table given in your book and now answer the following question:

Select three metals that can show disproportionation reaction.


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

Al, Cu, Fe, Mg and Zn.


Which of the following statement(s) is/are not true about the following decomposition reaction.

\[\ce{2KClO3 -> 2KCl + 3O2}\]

(i) Potassium is undergoing oxidation.

(ii) Chlorine is undergoing oxidation.

(iii) Oxygen is reduced.

(iv) None of the species are undergoing oxidation or reduction.


Identify the correct statements with reference to the given reaction.

\[\ce{P4 + 3OH- + 3H2O -> PH3 + 3H2PO^{-}2}\]

(i) Phosphorus is undergoing reduction only.

(ii) Phosphorus is undergoing oxidation only.

(iii) Phosphorus is undergoing oxidation as well as reduction.

(iv) Hydrogen is undergoing neither oxidation nor reduction.


\[\ce{MnO^{2-}4}\] undergoes disproportionation reaction in acidic medium but \[\ce{MnO^{-}4}\] does not. Give reason.


Assertion (A): The decomposition of hydrogen peroxide to form water and oxygen is an example of disproportionation reaction.

Reason (R): The oxygen of peroxide is in –1 oxidation state and it is converted to zero oxidation state in \[\ce{O2}\] and –2 oxidation state in \[\ce{H2O}\].


Write redox couples involved in the reactions given.

\[\ce{Cu + Zn^{2+} ->Cu^{2+} + Zn}\]


Write redox couples involved in the reactions given.

\[\ce{Fe + Cd^{2+} -> Cd + Fe^{2+}}\]


Which of the following statement is CORRECT for the decomposition reaction of KClO3

\[\ce{2KClO3 → 2KCl +3O2}\]


The reaction of sulphur in alkaline medium is given below:

\[\ce{S8(s) + {a} OH^-(aq) -> {b} S^{2-}(aq) + {c} S2O^{2-}3(aq) + {d} H2O(l)}\]

The values of 'a' are ______. (Integer answer)


In an experiment O3 undergo decomposition as \[\ce{O3 -> O2 + O}\] by the radiations of wavelength 310 Å. The total energy falling on the O3 gas molecules is 2.4 × 1026 eV and quantum yield of the reaction is 0.2.

The volume strength of the H2O2 solution which is obtained from reaction of 1 l H2O and nascent oxygen [O] obtained from the above reactions is (Assuming no change in volume of H2O)

\[\ce{H2O + O -> H2O2}\]

[Given: Na (Avogadro's No.) = 6 × 1023]


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×