Extraction of Metals low in the Activity Series Video Lecture - Class 10

after concentration we have got now
concentration gives us the PR now what
do we need to do with the Pierre Bureau
you need to get the metal from the
compound I'm not talking about gold
silver because after concentration of
gold silver you will get gold and silver
only but like zinc carbonate sodium
chloride you need to get the pure metal
out of the pure so in this case what
happens is that we need to separate the
metals into three groups metals of low
reactivity metals of medium reactivity
and metals of high reactivity so in this
case you will get copper mercury in this
you will get zinc make mostly and this
case you get aluminium sodium potassium
etcetera so if somebody asks you that
what type of reactivity does suppose
mercury have so what what is mercury
group under metal it is a is it a metal
of low reactivity medium reactivity or
high reactivity while extract okay this
question can be formed like while
extraction
what would you group mercury into that
is low reactivity medium reactivity or
high reactivity so the obvious answer is
low reactivity why we are seeing this is
that generally these metals of flow
reactivity have a common technique of
separation of extraction metals of
medium reactivity have a common
technique of extraction and metals of
highly activity have a common technique
of extraction so because actually metals
of high reactivity they will not want to
get separated and formed as the pure
metal so it is very difficult to
separate them using the techniques of
metal extracting metals with low
reactivity or medium reactivity so that
is why all the three have different
methods
so first we'll come to methods of low
reactivity
in this you have copper and mercury now
since they have low reactivity they
decompose you have at basically your how
you find these compounds as Cu 2 s and H
GS
both are sulfides
their ores are sulfides so these are
very weak sulfides I mean just by
heating you can get the oxide the thing
is that they just decompose on heating
what you do is that you take this just
heat it in the presence of oxygen or you
should write oxygen over here only
and you get hg o plus SOP so balance
this - that's for six well I think this
is balanced yeah
now you take this edge ooh
and again heat and you will get pure hg
and or just simple reaction first you
heat it with oxygen and you will get
sulphur dioxide gas and the oxide now
generally the oxide is easier it is it
is easier to obtain the metal from the
oxide rather than itself rhymes so we
first converted to the oxide and then
the oxide is heated again to give HT so
G is obtained very simply by just
heating and similarly with copper
sulphide so you might get questions like
X is heated X is an ore and it is heated
to get Y and Y is the pure metal so what
is X so it can be a GS because this is
by just heating you are getting the pure
metal from the earth and of course the
in in these type of questions you have
to give the reactions
in work very important otherwise you
might lose all the marks in the question
if you don't leave the reaction so these
two reactions are compulsive wherever if
they don't ask for reaction also but
there is a hint of reaction in the
question you should give the reaction
and if they ask then you definitely
should give the reaction and similarly
for cu2s this is slightly different
this is heated to give Cu 2 O plus so2
to so3 balance I know this yeah 2 + 4 6
3 ok no it's done and then you take this
Cu and of course as heat and you react
this with this you to us and he did and
you get Cu plus again so2 6
so slightly different reaction in this
first you get co2 and so2 and then you
heat it with the or itself you heat the
oxide with the over itself and you get
the pure metal and again the same gases
evolved so you might be asked questions
like X on heating gives Y and Y on
heating with X gives Z and there is a
gas G involved in both the reactions and
you're given that X is a node and Z is
the parameter so now you know but
because you have just seen the reaction
and now I'm asking but when you just get
a random question like this just try to
imagine that and oh you don't have
anything added to it it's just pure
heating and then you are getting the
pure metal 2 reactions you are getting
the pure metal so this has to be a metal
of low reactivity like copper or edgy
but an edg's reaction you might you
might have noticed that in the first
reaction so2 gases involved but in the
second reaction Oh two gases involved
even so these two gases cannot be seen
in case of ng
and also in a GU directly heated you
don't put X again in Hawaii over here
you don't have hg o plus h GS but in
case of copper now this is canceled so
only copper remains so in case of copper
you will see that this equation is
satisfied because copper sulfide will
give you copper oxide and so2 gas and
copper oxide again heated with copper
sulfide will give you copper and again
sots
so these X Y Zed questions you just try
to get go step by step like get a group
of things then try to eliminate one by
one so you got copper and mercury
because the OL was giving a pure metal
just by heating and then you saw that in
Mercury's reaction the gas evolved is
not the same and also there is no the
ore is not again added to this Y so the
remaining will be copper and then with
that what the remaining is we try to fit
it in the equation
you