redox reactions
No description yet. This curated deck is ready for daily study.
Card preview (22)
what is oxidation and reduction in terms of oxygen?
oxidation is the gaining of oxygen and reduction is the loss of oxygen.
what is oxidation and reduction in terms of hydrogen?
removal of hydrogen is called oxidation and addition of hydrogen is called reduction.
what are spectator ions?
ions that do not change number in a reaction.
what is oxidation and reduction in terms of electrons?
oxidation is the loss of electrons and reduction is the gain of electrons
what is the oxidising agent?
the ion that is accepting electrons as it causes oxidisation by being reduced.
what is the reducing agent?
the chemical donating electrons causing reduction of other species. It is oxidised themselves.
how do you know the oxidation number of an ion?
the oxidisation number is the same as the number of the ion e.g the ion, Mg2+, has oxidation number of +2
what does oxidation number tell us?
how many electrons are gained or lost in a reaction.
in a pure element, the atoms have an oxidation number of what?
zero including diatomic elements
when reacted, fluorine always have an oxidation number of what and why?
-1 as fluorine is the most electronegative element so no other element can remove an electron from fluorine
when reacted, oxygen usually has an oxidation number of what? however what are the exceptions?
-2 however in peroxides it is -1 and when reacted with fluorine it is +2 as fluorine is electronegative enough to remove electrons from oxygen
when reacted halogens (chlorine, bromine and iodine) usually have an oxidation number of what? however what are the exceptions?
-1 however they can have a positive oxidation number when reacted with fluorine or oxygen
when reacted what is usually the oxidation number of hydrogen? however what are the exceptions?
+1 however in metal hydrides the oxidation number is -1
what is the oxidation number of group 1 metals when they react?
always +1
what is the oxidation number of group 2 metals when they react?
always +2
what is the oxidation number of aluminium when it reacts?
always +3
what is the oxidation number of transition metals?
variable, depends on the compound, must be calculated
all the oxidation numbers of the atoms of a compound must add up to what?
to the total charge on the compound
describe oxidation and reduction in terms of oxidation numbers?
when oxidation number increases, it is oxidation. When the oxidation number decreases, it is reduction.
is the big number (number of molecules) considered when calculating oxidation numbers?
no
how are oxidation numbers presented?
using Roman numerals
what is a disproportionate reaction?
when an element is both oxidised and reduced in a reaction