IN NEED OF HELP PLEASE 1. When the following equation is balanced properly under
ID: 636136 • Letter: I
Question
IN NEED OF HELP PLEASE
1. When the following equation is balanced properly under acidic conditions, what are the coefficients of the species shown? Pb2+ + CuPb + Cu2+
Water appears in the balanced equation as a (reactant, product, neither) with a coefficient of . (Enter 0 for neither.)
How many electrons are transferred in this reaction?
2. When the following equation is balanced properly under acidic conditions, what are the coefficients of the species shown? SO2 + BrO3-SO42- + Br-
Water appears in the balanced equation as a (reactant, product, neither) with a coefficient of . (Enter 0 for neither.)
How many electrons are transferred in this reaction?
Explanation / Answer
1.
Pb+2 +Cu --------------- Pb + Cu+2
+2 0 0 +2
The oxidation state of Pb is decreases from +2 to 0, So it undergoes redcution
The oxidation state of Cu is increases from 0 to 2, So it undergoes oxidation.
Oxidation half reaction
Cu ---------------- Cu+2
Cu ------------- Cu+2 + 2e-
reduction half reaction
Pb+2 ------------- Pb
Pb+2 + 2e- ---------- Pb
Cu ------------- Cu+2 + 2e-
Pb+2 + 2e- ---------- Pb
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Cu + Pb+2 -------------- Pb + Cu+2
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This is net balanced equation.
water molecules are present neither side of the reaction.
2)
SO2 + BrO3- ----------------- SO4-2 + Br-
+4 +5 +6 -1
The oxidation state of S is increases from +4 to +6. So it undergoes oxidation
The oxidation state of Br is idecreases from +5 to -1. So it undegoes reduction.
Oxidation half reaction
SO2 ------------- SO4-2
SO2 + 2 H2O --------------- SO4-2
SO2 + 2 H2O --------------- SO4-2 + 4 H+
SO2 + 2 H2O --------------- SO4-2 + 4H+ +2e-
Reduction half reaction
BrO3- -------------------- Br-
BrO3- --------------- Br- + 3 H2O
BrO3- + 6 H+ -------------- Br- + 3 H2O
BrO3- + 6 H+ + 6e- -------------- Br- + 3 H2O
[SO2 + 2 H2O --------------- SO4-2 + 4H+ +2e-]x6
[BrO3- + 6 H+ + 6e- -------------- Br- + 3 H2O]x2
3 SO2 + 6 H2O ------------------ 3 SO4-2 + 12 H+ + 6e-
BrO3- + 6 H+ + 6e- ----------- Br- + 3 H2O
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3 SO2 + BrO3- + 3 H2O ------------- 3 SO4-2 + Br- + 6 H+
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This is balalced equation.
Three ( 3) moles Water molecules present on reactant side .
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