Term
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Definition
- The oxidation number of a free element is zero
- the oxidation number for a monoatomic ion is equal to the charge of the ion
- The oxidation number of each Group IA element in a compound is +1
- The oxidation number of each Group IIA element in a compound is +2
- The oxidation number of each Group VIIA element in a compound is -1, except when combined with an element of higher electronegativity
- the oxidation number of hydrogen is usually +1; however, its oxidation number is -1 in compounds with less electronegative elements (Groups IA and IIA)
- In most compounds the oxidation number of oxygen is -2.
- The sum of the oxidation number of all the atoms present in a neutral compound is zero. The sum of the oxidation numbers of the atoms present in a polyatomic ion is equal to the charge of the ion.
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Term
| Balancing oxidation-reduction reactions |
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Definition
- Separate the two half reactions
- Balance the atoms of each half reaction. Balance all atoms except H and O first. Then in acidic solution ad H2O to balance the O atoms and then add H+ to balance the H atoms. In basic solution, us OH- and H2O to balance the O and H atoms
- Balance the charges of each half reaction by adding electrons
- Multiply the half reactions so that each half reaction has the same number of electrons so they will cancel out
- Add the half reactions and cancel out
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Term
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Definition
| ignore spectator ions to focus only the species that actually participate in the reaction. |
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Term
net ionic equations:
combination reactions
decomposition reactions
combustion reactions
double-displacement (metathesis) reactions
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Definition
| all are oxidation reduction reactions except for double-displacement reactions that don't form a solid salt. If no solid salt is formed there is no net ionic reaction because all species stay in solution and their oxidation number doesn't change |
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Term
| disproportionation reactions |
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Definition
| aka dismutation reactions - a type of redox reaction in which one element is both oxidized and reduced, forming at least two molecules containing the element with different oxidation states |
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Term
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Definition
| use voltage as an indicator as opposed to pH like acid-base titrations |
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Term
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Definition
| a form of redox titration in which a voltmeter or external cell measures the electromotive force (emf) of a solution. No indicator is used, and the equivalence point is determined by a sharp change in voltage |
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