English
Karnataka Board PUCPUC Science Class 11

Justify that the Following Reactions Are Redox Reactions: 4bcl3(G) + 3lialh4(S) → 2b2h6(G) + 3licl(S) + 3 Alcl3 (S)

Advertisements
Advertisements

Question

Justify that the following reaction is redox reaction:

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

Numerical
Advertisements

Solution

The oxidation number of each element in the given reaction can be represented as:

 +3 -1            +1 +3 -1                -3  +1            +1  -1           +3  -1
\[\ce{4BCl3(g) + 3LiAlH4(s) → 2B2H6(g) + 3LiCl(s) + 3 AlCl3(s)}\]

In this reaction, the oxidation number of B decreases from +3 in BCl3 to –3 in B2H6. i.e., BCl3 is reduced to B2H6. Also, the oxidation number of H increases from –1 in LiAlH4 to +1 in B2H6 i.e., LiAlH4 is oxidized to B2H6. Hence, the given reaction is a redox reaction.

shaalaa.com
  Is there an error in this question or solution?
Chapter 7: Redox Reactions - EXERCISES [Page 280]

APPEARS IN

NCERT Chemistry Part 1 and 2 [English] Class 11
Chapter 7 Redox Reactions
EXERCISES | Q 8.3 - (c) | Page 280

RELATED QUESTIONS

Justify that the following reaction is redox reaction:

\[\ce{2K(s) + F2(g) → 2K+F– (s)}\]


Justify that the following reaction is redox reaction:

\[\ce{4 NH3(g) + 5 O2(g) → 4NO(g) + 6H2O(g)}\]


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?


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:

\[\ce{Pb(s) + PbO2(s) + 2H2SO4(aq) → 2PbSO4(s) + 2H2O(l)}\]


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.


Consider the reactions:

  1. \[\ce{H3PO2(aq) + 4 AgNO3(aq) + 2 H2O(l) → H3PO4(aq) + 4Ag(s) + 4HNO3(aq)}\]
  2. \[\ce{H3PO2(aq) + 2CuSO4(aq) + 2 H2O(l) → H3PO4(aq) + 2Cu(s) + H2SO4(aq)}\]
  3. \[\ce{C6H5CHO(l) + 2[Ag (NH3)2]+(aq) + 3OH–(aq) → C6H5COO–(aq) + 2Ag(s) + 4NH3 (aq) + 2 H2O(l)}\]
  4. \[\ce{C6H5CHO(l) + 2Cu^{2+}(aq) + 5OH–(aq) → No change observed}\]

What inference do you draw about the behaviour of Ag+ and Cu2+ from these reactions?


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.


Which of the following elements does not show disproportionation tendency?


Assertion (A): Redox couple is the combination of oxidised and reduced form of a substance involved in an oxidation or reduction half cell.

Reason (R): In the representation \[\ce{E^Θ_{Fe^{3+}/Fe^{2+}}}\] and \[\ce{E^Θ_{Cu^{2+}/Cu}, Fe^{3+}/Fe^{2+}}\] and \[\ce{Cu^{2+}/Cu}\] are redox couples.


Write redox couples involved in the reactions given.

\[\ce{Br2 + 2Cl- -> Cl2 + 2Br-}\]


An acidified manganate solution undergoes disproportionation reaction. The spin-only magnetic moment value of the product having manganese in a higher oxidation state is ______ B.M. (Nearest integer)


The species given below that does NOT show a disproportionation reaction is ______.


\[\ce{H2O2 -> H2O + O2}\]

This represents ______.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×