redox reactions
Cards (7)
- what are redox reactions?
- redox stands for reduction and oxidation reactions
- redox reactions involve the transfer of e- (electrons)
- redox reaction is comprised of two half equations:
- oxidation: loss of electrons (OIL)
- reactant of this reaction = reductant
- what are redox reactions?
- redox stands for reduction and oxidation reactions
- redox reactions involve the transfer of e- (electrons)
- redox reaction is comprised of two half equations:
- oxidation: loss of electrons (OIL)
- reactant of this reaction = reductant
- reduction: gain of electrons (RIG)
- reactant of this reaction = oxidant
- what are the oxidation number rules?
- The oxidation number of an element in its elemental form is zero. 2. The sum of oxidation numbers = overall charge 3. for ions, the oxidation number = charge e.g. Na+ = +1 4. Oxygen usually has an oxidation number of -2, unless it is in a peroxide where it is -1. (H2O2) 5. Hydrogen usually has an oxidation number of +1, unless it is in a hydride where it is -1.
- how to identify reduction and oxidation reactions?
- oxidation reaction: reducant's (reactant) oxidation number will increase
- reduction reaction: oxidant's (reactant) oxidation number will decrease
- steps:
- identify conjugate pairs
- identify oxidation + reduction reaction (oxidation number increase or decrease)
- label reductant + oxidant
- what are the steps to write half equation in acidic conditions (acidic is implied unless mentioned otherwise?KOHES
- key elements (not oxygen or hydrogen)
- Oxygen (+H2O)
- hydrogen (+H+)
- electrons (e-) -> balance charge
- states
- what are the steps to write half equations in basic/alkaline conditions?
- KOHES
- nH+ -> add nOH- to BOTH SIDES
- nH+(aq) + nOH-(aq) -> nH2O(l)
- cancel down H2O
- how to go from full equations to half equations?
- identify oxidant and reductant reactants and their conjugates using oxidation numbers (ignore H2O or H+)
- balance half equation
*change in oxidation number = e-