University:
Eastern Kentucky University
Course:
CHE 111 | General Chemistry
Academic year:

2020
Views:

335

Pages:

1
Author:

Zoie Hudson

General Chemistry 11: Oxidation-Reduction Reactions Definitions Oxidation: Loss of eReduction: Gain of eWith Respect to Oxidation is GAIN of oxygen Oxygen Transfer: Reduction is LOSS of oxygen Oxidizing Agent: Facilitates the oxidation of another compound. Is itself reduced Reducing Agent: Facilitates the reduction of another compound. Is itself oxidized Balancing via Half-Reaction Method • • • • • • Separate the two half-reactions Balance the atoms of each half-reaction. Start with all elements besides H and O. In acidic solution, balance H and O using water and H+. In basic solution, balance H and O using water and OHBalance the charges of each half-reaction by adding e- as necessary Multiply the half-reactions as necessary to obtain the same number of e- in both half-reactions Add the half-reactions, canceling out terms on both sides Confirm that the mass and charge are balanced Oxidation # Rules • • • • • • • Any free element or diatomic species = 0 Monatomic ion = the charge of the ion When in compounds, group 1A metals = +1; group 2A metals = +2 When in compounds, group 7A elements = -1, unless combined with an element of greater EN H = +1 unless it is paired with a less EN element, then = -1 O = -2 except in peroxides, when it = -1, or in compounds with more EN elements The sum of all oxidation numbers in a compound must = overall charge Net Ionic Equations Complete Ionic Equation: Accounts for all of the ions present in a reaction. Split all aqueous compounds into their relevant ions. Keep solid salts intact. Net Ionic Equation: Ignores spectator ions Disproportionation Reactions: A type of REDOX reaction in which one element is both (dismutation) oxidized and reduced, forming at least two molecules containing the element with different oxidation states REDOX Titrations:Similar in methodology to acid-base titrations, however, these titrations follow transfer of charge Potentiometric Titration: A form of REDOX titration in which a voltmeter measures the electromotive force of a solution. No indicator is used, and the equivalence point is determined by a sharp change in voltage