Redox Reactions Flashcards
refers to a reaction in which a species gains electrons
reduction (GER)
refers to a reaction in which a species gives up or loses electrons
oxidation (LEO)
gets reduced during reaction
oxidizes something else–causes the species giving up the electrons to be oxidized
oxidizing agent
Since electrons cannot be created or destroyed and there can be no isolated loss or gain of electrons, neither oxidation or reduction can occur _______, resulting in an electron transfer between 2 species
by itself
The electrons released during ______ are taken up in the ______ process.
released during oxidation
taken up during reduction
substance that gets oxidized
reduces something else
causes another species to be reduced
reducing agent
an oxidizing agent get _______ and _____ electrons
reduced
gain electrons
a reducing agent gets ______ and _____ electrons
oxidized
loses electrons
the oxidation number of an element in its elemental form =
Ex: N2, O2, He, etc.
zero
The oxidation state of a monatomic ion is the same as its ______
charge
In molecules w/ 2 different elements, the elements w/ the greater ________ is assigned a negative oxidation number = to its charge in simple ionic compounds of the element
electronegativity
Sum of the oxidation numbers = _____ for an electrically neutral compounds and equals the overall charge for an ionic species
zero
Oxidation numbers for alkali metals (group I)
+1
oxidation numbers for alkaline earth metals (group II)
+2
oxidation number for group 3A
+3
Oxidation number for halogens
-1 except when combo’ed w/ an element of high electronegativity
Oxidation number for Oxygen
-2
Oxidation number of Hydrogen when bonded to a more electronegative element (most nonmetals) =
+1
Oxidation number of Hydrogen when bonded to a less electronegative element (most metals) =
-1
a complex redox rxn can be separated into these component rxns
elements other than H and O should be balanced
half reactions
in balancing REDOX rxns, the loss and gain of electrons is indicated where appropriate
charge is then balanced w _____ when in acid or _____ when in base. Elements O and H are then balanced with _____
H+: acid
OH-: base
H20: water
each half-rxn is multiplied by an appropriate factor so that the number of electrons gained _______ those lost
rxns are then combined to form the net rxn
equal
contained system in which a redox reaction occurs in conjuction with the passage of electric current
2 types: galvanic and electolytic
electrochemical cell
2 types of electrochemical cell
galvanic (or voltaic)
electrolytic