Ch 20: Oxidation-Reduction Reactions Flashcards
The substance gaining oxygen is ________, while the substance losing oxygen is _______.
oxidized
reduced
Loss of electrons is…
Oxidation
Where does oxidation take place?
Anode
Gain of electrons is…
Reduction
Where does reduction take place?
Cathode
_________ flow from anode to cathode.
Electrons
An __, Red ___
Ox
Cat
__ Ox, ___ Cat
An
Red
_IL _IG
OIL RIG
Oxidation and reduction happen…
together.
How the ions travel between cells to keep the charge balanced is…
the salt bridge.
Depends on reactivity and more reactive substances have more potential is…
Cell potential (volts)
______ electrons is oxidation. _______ electrons is reduction.
Losing
Gaining
Iron, a common construction metal often used in the form of the _____ steel, corrodes by being ________ to ions of iron by oxygen.
alloy
oxidized
As a general rule, a bonded atom’s _________ ______ is a charge that it would have if the electrons in the bond were assigned to the atom of the more electronegative element.
oxidation number
The oxidation number of a monatomic ion is equal in magnitude and sign to its _____ charge.
ionic
Rule: ions =
to charge
The oxidation number of hydrogen in a compound is…
+1
Rule: hydrogen in compounds =
+1
Rule: oxygen in compounds =
-2
Rule: elements =
0
Rule: sum =
to charge
An increase in the oxidation number of an atom or ion indicates _________. A decrease in the oxidation number of an atom or ion indicates ________.
oxidation
reduction
If the oxidation number of an element in a reacting species changes, then that element has undergone either oxidation or reduction. Therefore, the reaction as a whole must be a _____ reaction.
redox
In a balanced redox equation, the total increase in oxidation number of the species oxidized must be balanced by the total ________ in the oxidation number of the species _______.
decrease
reduced
To balance a redox equation using half-rections, write separate half-reaction for the oxidation and the reduction. After you balance atoms in each half-reaction, balance _________ gained in the reduction with electrons lost in the oxidation.
electrons
Electrochemical cells
Batteries
Electrolysis
Battery rechargers
Change chemical energy into electrical energy.
Electrochemical cells
Change electrical energy into chemical energy.
Electrolysis
