Advertisements
Advertisements
Question
Write balanced chemical equation for the following reactions:
Permanganate ion \[\ce{(MnO^{-}4)}\] reacts with sulphur dioxide gas in acidic medium to produce \[\ce{Mn^{2+}}\] and hydrogen sulphate ion.
Advertisements
Solution
\[\ce{2MnO^{-}4 + 5SO2 + 2H2O + H+ -> 5HSO^{-}4 + 2Mn^{2+}}\]
Balancing by ion-electron method:
\[\ce{\overset{+7}{Mn}\overset{-2}{O}^{-}4 + \overset{+4}{S}\overset{-2}{O2} -> \overset{+2}{Mn}^{2+} + \overset{+1}{H}\overset{+6}{S}\overset{-2}{O}^{-}4}\] (Skeletal equation)
Oxidation half: \[\ce{SO2 -> HSO^{-}4}\]
Reduction half: \[\ce{MnO^{-}4 -> Mn^{2+}}\]
Oxidation half: \[\ce{SO2 -> HSO^{-}4 + 2e-}\]
\[\ce{SO2 + 2H2O -> HSO^{-}4 + 3H^{+} + 2e-}\] ......(i)
(Add \[\ce{2H2O}\] molecules to balance \[\ce{O}\] atoms)
Reduction half:
\[\ce{MnO^{-}4 + 5e- -> Mn^{2+}}\]
\[\ce{MnO^{-}4 + 8H^{+} + 5e- -> Mn^{2+} + 4H2O}\] ......(ii)
(Add \[\ce{4H2O}\] molecules to balance \[\ce{O}\] atoms and \[\ce{H}\] atoms)
Add oxidation and reduction half
\[\ce{[SO2 + 2H2O -> HSO^{-}4 + 3H+ + 2e-] × 5}\]
\[\ce{[MNO^{-}4 + 8H+ + 5e- -> Mn^{2+} + 4H2O] × 2}\]
\[\ce{2MNo^{-}4 + 5SO2 + 2H2O + H+ -> 5HSO^{-}4 + 2Mn^{2+}}\]
APPEARS IN
RELATED QUESTIONS
Calculate the oxidation number of sulphur, chromium and nitrogen in H2SO5, `"Cr"_2"O"_7^(2-)` and `"NO"_3^-`. Suggest structure of these compounds. Count for the fallacy.
Consider the reaction:
\[\ce{O3(g) + H2O2(l) → H2O(l) + 2O2(g)}\]
Why it is more appropriate to write these reaction as:
\[\ce{O3(g) + H2O2 (l) → H2O(l) + O2(g) + O2(g)}\]
Also, suggest a technique to investigate the path of the redox reactions.
The compound AgF2 is an unstable compound. However, if formed, the compound acts as a very strong oxidizing agent. Why?
Whenever a reaction between an oxidising agent and a reducing agent is carried out, a compound of lower oxidation state is formed if the reducing agent is in excess and a compound of higher oxidation state is formed if the oxidising agent is in excess. Justify this statement giving three illustrations.
How do you count for the following observations?
Though alkaline potassium permanganate and acidic potassium permanganate both are used as oxidants, yet in the manufacture of benzoic acid from toluene we use alcoholic potassium permanganate as an oxidant. Why? Write a balanced redox equation for the reaction.
Balance the following redox reactions by ion-electron method:
- \[\ce{MnO-_4 (aq) + I– (aq) → MnO2 (s) + I2(s) (in basic medium)}\]
- \[\ce{MnO-_4 (aq) + SO2 (g) → Mn^{2+} (aq) + HSO-_4 (aq) (in acidic solution)}\]
- \[\ce{H2O2 (aq) + Fe^{2+} (aq) → Fe^{3+} (aq) + H2O (l) (in acidic solution)}\]
- \[\ce{Cr_2O^{2-}_7 + SO2(g) → Cr^{3+} (aq) + SO^{2-}_4 (aq) (in acidic solution)}\]
Balance the following equation in the basic medium by ion-electron method and oxidation number methods and identify the oxidising agent and the reducing agent.
\[\ce{N2H4(l) + ClO^-_3 (aq) → NO(g) + Cl–(g)}\]
The Mn3+ ion is unstable in solution and undergoes disproportionation to give Mn2+, MnO2, and H+ ion. Write a balanced ionic equation for the reaction.
In Ostwald’s process for the manufacture of nitric acid, the first step involves the oxidation of ammonia gas by oxygen gas to give nitric oxide gas and steam. What is the maximum weight of nitric oxide that can be obtained starting only with 10.00 g. of ammonia and 20.00 g of oxygen?
Justify that the following reaction is redox reaction; identify the species oxidized/reduced, which acts as an oxidant and which acts as a reductant.
\[\ce{2Cu2O_{(S)} + Cu2S_{(S)}->6Cu_{(S)} + SO2_{(g)}}\]
Balance the following reaction by oxidation number method.
\[\ce{MnO^-_{4(aq)} + Br^-_{ (aq)}->MnO2_{ (s)} + BrO^-_{3(aq)}(basic)}\]
Balance the following redox equation by half-reaction method.
\[\ce{Bi(OH)_{3(s)} + SnO^2-_{2(aq)}->SnO^2-_{3(aq)} + Bi^_{(s)}(basic)}\]
Identify coefficients 'x' and 'y' for the following reaction.
\[\ce{{x}H2O2_{(aq)} + ClO^-_{4(aq)} -> 2O2_{(g)} + ClO^-_{2(aq)} + {y}H2O_{(l)}}\]
Which of the following is a redox reaction?
Consider the reaction:
\[\ce{6 CO2(g) + 6H2O(l) → C6 H12O6(aq) + 6O2(g)}\]
Why it is more appropriate to write these reaction as:
\[\ce{6CO2(g) + 12H2O(l) → C6 H12O6(aq) + 6H2O(l) + 6O2(g)}\]
Also, suggest a technique to investigate the path of the redox reactions.
Balance the following equations by the oxidation number method.
\[\ce{I2 + S2O^{2-}3 -> I- + S4O^{2-}6}\]
Identify the redox reactions out of the following reactions and identify the oxidising and reducing agents in them.
\[\ce{3HCl (aq) + HNO3 (aq) -> Cl2 (g) + NOCl (g) + 2H2O (l)}\]
Identify the redox reactions out of the following reactions and identify the oxidising and reducing agents in them.
\[\ce{PCl3 (l) + 3H2O (l) -> 3HCl (aq) + H3PO3 (aq)}\]
In acidic medium, reaction, \[\ce{MNO^-_4 → Mn^2+}\] an example of ____________.
