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प्रश्न
What sorts of informations can you draw from the following reaction ?
\[\ce{{(CN)}_{2(g)} + 2OH-_{(aq)} -> CN-_{(aq)} + CNO-_{(aq)} + H_2O_{(l)}}\]
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उत्तर
The oxidation numbers of carbon in (CN)2, CN– and CNO– are +3, +2 and +4 respectively. These are obtained as shown below:
Let the oxidation number of C be x.
(CN)2
2(x – 3) = 0
∴ x = 3
CN–
x – 3 = –1
∴ x = 2
CNO–
x – 3 – 2 = –1
∴ x = 4
The oxidation number of carbon in the various species is:
\[\ce{{(^{+3}CN)}_{2(g)} + 2OH-_{(aq)} -> ^{+2}CN-_{(aq)} + ^{+4}CNO-_{(aq)} + H_2O_{(l)}}\]
It can be easily observed that the same compound is being reduced and oxidised simultaneously in the given equation. Reactions in which the same compound is reduced and oxidised is known as disproportionation reactions. Thus, it can be said that the alkaline decomposition of cyanogen is an example of disproportionation reaction.
संबंधित प्रश्न
Justify that the following reaction is redox reaction:
\[\ce{CuO(s) + H2(g) → Cu(s) + H2O(g)}\]
Justify that the following reaction is redox reaction:
\[\ce{4 NH3(g) + 5 O2(g) → 4NO(g) + 6H2O(g)}\]
Suggest a list of the substances where carbon can exhibit oxidation states from –4 to +4 and nitrogen from –3 to +5.
How do you count for the following observations?
When concentrated sulphuric acid is added to an inorganic mixture containing chloride, we get colourless pungent-smelling gas HCl, but if the mixture contains bromide then we get red vapour of bromine. Why?
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:
\[\ce{HCHO (l) + 2Cu^{2+}(aq) + 5 OH–(aq) → Cu2O(s) + HCOO–(aq) + 3H2O(l)}\]
Identify the substance oxidised, reduced, oxidising agent and reducing agent for the following reaction:
\[\ce{N2H4(l) + 2H2O2(l) → N2(g) + 4H2O(l)}\]
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 is not an example of redox reaction?
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.
\[\ce{Br2 + 2Cl- -> Cl2 + 2Br-}\]
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Which of the following reactions is the metal displacement reaction? Choose the right option.
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)
The species given below that does NOT show a disproportionation reaction is ______.
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]
