M3 Topic 2: Predicting Reactions of Metals Flashcards
what is a redox reaction
refers to a simultaneous oxidation and a reduction reaction
what happens in a oxidation reaction
where solid element loses electrons to become a ion
what happens in a reduction reaction
where ions gain electrons to form a solid element
what are oxidation numbers used for
is used to determine if a particular element is oxidised or reduced
what is the oxidation number for element in elemental state
0
what is the oxidation number of oxygen
-2 except in peroxides where it is -1
what is the oxidation number of hydrogen
+1 except in metal hydroxide -1
what does the sum of oxidation numbers add up to
the charge on the species
in a redox reaction what does a higher Oxidation number mean
the species oxidised
in a redox reaction what does a lower Oxidation number mean
the species reduced
what is a galvanic cell
deceives that use chemical reaction to create electricity
what are the main parts of a galvanic cell (3)
anode
cathode
salt bridge
what is the anode
the sight of oxidation (+)
what is the cathode
the sight of reduction (-)
what does the salt bridge do (2)
Completes the circuit
Balances out charge by releasing ions to ensure no + and - build up
