Question

Write balanced net ionic equations for the following reactions in basic solution.

A. S2O32−(aq)+I2(aq)→S4O62−(aq)+I−(aq)

Express your answer as a chemical equation. Identify all of the phases in your answer.

Part B Mn2+(aq)+H2O2(aq)→MnO2(s)+H2O(l)

Part C Zn(s)+NO3−(aq)→NH3(aq)+Zn(OH)42−(aq)

Part D Bi(OH)3(s)+Sn(OH)3−(aq)→Bi(s)+Sn(OH)62−(aq)

Answer 1

NOTE :-

Follow the following steps while balancing the Redox reaction by ion-exchange method :-

Step.1 :- Write and balance the oxidation and reduction half cell reactions separately.

Step.2 :- Balance the atoms other than hydrogen and oxygen

Step.3 :- Balance the oxygen atom by adding suitable number of H₂O on the oxygen deficient side.

Step.4 :- After that balance the hydrogen atom by adding suitable number of H⁺ on the hydrogen deficient side.

Step.5 :- Finally balance the charge on both side by adding suitable number of electrons.

Step.6 :- First balance the equation in acidic medium and then converted this equation in basic medium by adding same number of moles of OH^- ( as that of H⁺) on both the sides.

1.

Balanced Oxidation half cell reaction is :

2 S₂O₃²⁻(aq) ----------------> S₄O₆²⁻(aq) + 2e^-

Balanced Reduction half cell reaction is :

I₂ (aq) + 2e^- --------------> 2 I^- (aq)

Adding both the half cell reaction, we have balanced chemical equation in basic medium is :

2 S₂O₃²⁻(aq) + I₂ (aq) ---------------> S₄O₆²⁻(aq) + 2 I^- (aq)

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2.

Balanced Oxidation half cell reaction is :

Mn²⁺(aq) + 2 H₂O (l) ----------------> MnO₂(s) + 2e^- + 4 H⁺ (aq)

Adding 4 OH^- on both sides in order to write equation in basic medium, we have

Mn²⁺(aq) + 4 OH^- (aq) ----------------> MnO₂(s) + 2e^- + 2 H₂O (l)

Balanced Reduction half cell reaction is :

H₂O₂(aq) + 2 H⁺ (aq) + 2e^- --------------> 2 H₂O(l)

Adding 2 OH^- on both sides in order to write equation in basic medium, we have

H₂O₂(aq) + 2e^- --------------> 2 OH^- (aq)

Adding both the half cell reaction, we have balanced chemical equation in basic medium is :

Mn²⁺(aq) + H₂O₂(aq) + 2 OH^- (aq) --------------> MnO₂(s) + 2 H₂O (l)