Chemistry Chapter 11: Oxidation-Reduction Reactions (2 Stars) Flashcards
(27 cards)
______ is a loss of electrons, and _____ is a gain of electrons; the two are paired together in what is known as an oxidation–reduction (redox) reaction.
Oxidation
reduction
An ______ agent facilitates the oxidation of another compound and is reduced itself in the process; a reducing agent facilitates the reduction of another compound and is itself oxidized in the process.
oxidizing
Common oxidizing agents almost all contain _____ or a similarly electronegative element.
oxygen
Common reducing agents often contain _____ ions or hydrides (H– ).
metal
To assign oxidation numbers, one must know the common oxidation _____ of the representative elements.
states
Any free element or diatomic species has an oxidation number of _____
zero.
The oxidation number of a monatomic ion is equal to the _____ of the ion.
charge
When in compounds, Group IA metals have an oxidation number of #____; Group IIA metals have an oxidation number of #____.
+1
+2.
When in compounds, Group VIIA elements have an oxidation number of #____ (unless combined with an element with higher electronegativity).
-1
The oxidation state of hydrogen is #___ unless it is paired with a less electronegative element, in which case it is –1.
+1
The oxidation state of oxygen is usually #___, except in peroxides (when its charge is –1) or in compounds with more electronegative elements.
-2
The sum of the oxidation numbers of all the atoms present in a compound is equal to the overall ___ of that compound.
charge
When balancing redox reactions, the half-reaction method, also called the ______ , is the most common.
ion–electron method,
Separate the #____ half-reactions.
two
Balance the atoms of each half-reaction. Start with all the elements besides __ and ___. In acidic solution, balance H and O using water and H+ . In basic solution, balance H and O using water and OH– .
H and O
Balance the charges of each half-reaction by ____ electrons as necessary to one side of the reaction.
adding
____ the half-reactions as necessary to obtain the same number of electrons in both half-reactions. GeneralChem_2016.indb 386 4/13/16 3:11 PM 11: Oxidation–Reduction Reactions 387
Multiply
___ the half-reactions, canceling out terms on both sides of the reaction arrow.
Add
Confirm that the ____ and charge are balanced.
mass
A ____ ionic equation accounts for all of the ions present in a reaction. To write a complete ionic reaction, split all aqueous compounds into their relevant ions. Keep solid salts intact.
complete
Net ionic equations ignore ______ to focus only on the species that actually participate in the reaction. To obtain a net ionic reaction, subtract the ions appearing on both sides of the reaction, which are called spectator ions.
spectator ions
For reactions that contain no _____ salts, the net ionic equation is generally the same as the overall balanced reaction.
aqueous salts
For double displacement (metathesis) reactions that do not form a solid salt, there is no net ionic reaction because all ions remain in solution and do/ do not change oxidation number.
do not
________ reactions are 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.
Disproportionation (dismutation)
