a5_balancing redox worksheet i

Balancing Redox Reactions: Use separate sheet of paper! Using the rules for determining oxidation numbers ﬁnd the oxidation numbers for all the elements in each of the substances. Oxidation numbers can have fractions, for example, NaO2 : Na = +1; O = -1/2. 1. K2SO4 K ___; S ___ ; O ___ 3. Al2O3 Al ___; O ___ 5.CH3F C ___; H __; F __ 2. KMnO4 K ___; Mn ___; O ___ 4. CaH2 Ca___; H ___ 6. HSbF6 H__; Sb___; F__ Balance the reactions Balance the following reactions. Write the balanced half reactions. Identify the oxidation and the reduction, as well as the oxidizing agent and the reducing agent. Show all work! For example; Mn 2+ + ClO3 – + H2O ➔ MnO2 + Cl – + H + Oxidation # +2 +5 -2 +1 -2 +4 -2 -1 1+ {Mn and Cl are changing ox. numbers} Oxidation : Mn 2+ ➔ MnO2 + 2e – reducing agent = Mn 2+ Reduction : ClO3 – + 6e – ➔ Cl – oxidizing agent = ClO3 – (loses Oʼs) Balanced electrons: 3Mn 2+ + ClO3 – ➔ 3MnO2 + Cl – Balance charge: 3Mn 2+ + ClO3 – ➔ 3MnO2 + Cl – + 6H + Balance Hʼs & Oʼs: 3Mn 2+ + ClO3 – + 3H2O ➔ 3MnO2 + Cl – + 6H + {if basic reaction with OH – , add another step. Add OH – to both sides & H + +OH – =H2O} Balance OH – with H + : 3Mn 2+ + ClO3 – + 3H2O ➔ 3MnO2 + Cl – + 6H + (+ 6 OH – to both sides) 6OH – + 3Mn 2+ + ClO3 – + 3H2O ➔ 3MnO2 + Cl – + 6H2O (adjust H2O to one side) 6OH – + 3Mn 2+ + ClO3 – ➔ 3MnO2 + Cl – + 3 H2O 1. CH4 + NO ➔ N2 + CO2 + H2O 2. NH3 + O2 ➔ NO + H2O 3. Ag + H + + NO3 – ➔ Ag + + H2O + NO 4. H2O2 + MnO4 – + H + ➔ Mn 2+ + H2O + O2 5. PbO + V 3+ + H2O ➔ PbO2 + VO 2+ + H + 6. IO4 – + I – + H + ➔ I2 + H2O 7. S8 + O2 + H2O ➔ H2SO4 + H + 8. BaCrO4 + Fe 2+ + H + ➔ Ba 2+ + Cr 3+ + Fe 3+ + H2O 9. Fe2S3 + O2 + H2O ➔ Fe(OH)3 + S8 10.I2 + H5IO6 + ➔ IO3 – + H2O + H + Basic Solutions 11. CrI3 + H2O2 + OH – ➔ CrO4 – + IO4 – + H2O 12.As2S3 + H2O2 + OH – ➔ AsO4 – + SO4 2– + H2O 13. XeF6 + OH – ➔ XeO6 4– + Xe + O2 + F – + H2O 14.CH3OH + MnO4 – ➔ HCOO – + MnO2 + OH – + H2O from Hill and Petrucci Name _________________________________ Date _____________ Period ___

Upload: fanfans-keeroro

Post on 09-Nov-2015

5 views

Category:

Documents

2 download

Report

Download

Embed Size (px):

DESCRIPTION

Balancing Redox

TRANSCRIPT

Balancing Redox Reactions:Use separate sheet of paper!Using the rules for determining oxidation numbers find the oxidation numbers for all the elements in each of the substances. Oxidation numbers can have fractions, for example, NaO2 : Na = +1; O = -1/2.

1. K2SO4 K ___; S ___ ; O ___ 3. Al2O3 Al ___; O ___ 5.CH3F C ___; H __; F __2. KMnO4 K ___; Mn ___; O ___ 4. CaH2 Ca___; H ___ 6. HSbF6 H__; Sb___; F__

Balance the reactionsBalance the following reactions. Write the balanced half reactions. Identify the oxidation and the reduction, as well as the oxidizing agent and the reducing agent.Show all work!

For example; Mn2+ + ClO3 + H2O MnO2 + Cl + H+Oxidation # +2 +5 -2 +1 -2 +4 -2 -1 1+ {Mn and Cl are changing

ox. numbers}

Oxidation : Mn2+ MnO2 + 2e reducing agent = Mn2+Reduction : ClO3 + 6e Cl oxidizing agent = ClO3

(loses Os)Balanced electrons: 3Mn2+ + ClO3 3MnO2 + Cl Balance charge: 3Mn2+ + ClO3 3MnO2 + Cl + 6H+Balance Hs & Os: 3Mn2+ + ClO3 + 3H2O 3MnO2 + Cl + 6H+

{if basic reaction with OH, add another step. Add OH to both sides & H++OH=H2O}Balance OH with H+: 3Mn2+ + ClO3 + 3H2O 3MnO2 + Cl + 6H+ (+ 6 OH to both sides) 6OH + 3Mn2+ + ClO3 + 3H2O 3MnO2 + Cl + 6H2O(adjust H2O to one side) 6OH + 3Mn2+ + ClO3 3MnO2 + Cl + 3 H2O

1. CH4 + NO N2 + CO2 + H2O2. NH3 + O2 NO + H2O3. Ag + H+ + NO3 Ag+ + H2O + NO4. H2O2 + MnO4 + H+ Mn2+ + H2O + O25. PbO + V3+ + H2O PbO2 + VO2+ + H+6. IO4 + I + H+ I2 + H2O7. S8 + O2 + H2O H2SO4 + H+8. BaCrO4 + Fe2+ + H+ Ba2+ + Cr3+ + Fe3+ + H2O9. Fe2S3 + O2 + H2O Fe(OH)3 + S810. I2 + H5IO6 + IO3 + H2O + H+

Basic Solutions11.CrI3 + H2O2 + OH CrO4 + IO4 + H2O12.As2S3 + H2O2 + OH AsO4 + SO42 + H2O13.XeF6 + OH XeO64 + Xe + O2 + F + H2O14.CH3OH + MnO4 HCOO + MnO2 + OH + H2O from Hill and Petrucci

Name _________________________________ Date _____________ Period ___