Borax Video Lecture | Chemistry for JEE Main & Advanced

hello friends this video on p-bog
elements part 12 is brought to you by
example a calm no more fear from exam
they are various compounds of boron what
is the borax
there's also Malika's in Curtis diary
and the fourth is boron try a light so
we'll discuss all these compounds now
the first is the borax the go let's do
something like this is very important
compound of Peru and it's formula is any
to be 407 10s to or if you want to get
by to this is fashion also both are same
as Li Na to be 405 OS for we - did you
see the structure of board you see this
is actually cation with a positive
charge if you see there sorry negatively
charged anion this is -2 charge rail is
-2 charge and then here you add sodium 2
ions of sodium and then we have 8 what
molecules and here here you have eight
water molecules will the structure of
borax if you see the way it is linked is
they have four Boron's want to keep for
Boron's and all these are linked with
oxygen in this fashion in this oxygen
here also right and these are all these
photons now are linked with which
molecules right and now if you see these
guys have two negative charge that these
bonds if you see these are sp2
hybridized and these are sp3 hybridized
1 2 3 4 1 SP 2 hybridized 1 2 3 bonus
one other place and these two bonds has
which are sp3 hybridized has negative
charge so overall red have -2 negative
charge it's a mine and this is sodium
cation in a class and it has if you see
now this has extra 8 molecules of water
the total if you add if you see right
one
how many hydrogen molecules 1 2 3 4 4
hydrogen molecules and that means two
water molecules right because it has ten
water molecule but if you want write a
conceived structure as shows torture
this is like this because two sodium ion
have then I have this plus 2 this is
minus 2 this ionic actually this is a
time this whole thing is a mine with the
minus 2 charge and then I have a
molecule of water but the really complex
to write in this fashion so we write any
two before 7.10 st but this is the
actual formula for the garage this is
the shape if you see your three
dimensional ABC these are my Boron's
the pink ones are the photons and let me
write this is the structure of
three-dimensional structure of borax so
as we have told the board undergoes sp2
and sp3 rotation as I told these are sp3
hybridized and these are the other Mansa
sp2 derivatives right 2 SP 2 n 2 SP 3
feminists let's understand let's
understand something more and borax so
the first thing you can see this is a
crystalline white crystalline solid as
you can see here itself the second
property is it is dissolved in water so
it does not dissolve in cold water but
in hot water it dissolves doesn't
dissolve but what what it dissolved form
alkylene Sarmatian this is the reaction
we have this is now borax it reacts with
water cold water hot water who gives
sodium hydroxide and if you see this is
a strong base and I told this boric acid
is a weak acid so it's a strong as we
acid in strong base so it's a basic
solid or alkaline salt
alright on heating this
borax it lose water molecules first and
then swells up and further heating it
turns into a transparent liquid but when
this liquid solidifies with some other
metals it gives color to the class it
comes with a glass shape actually will
be swollen foil it becomes a class shape
and then this glass actually need heat
this class with some metals it gives
different colors
correct and this is used to declare my
mental example manganese will give you
Blanca this is wrong miss Maggie's with
you brown right chromium will give you a
green color right copper will also give
you a green color nickel will give you a
brown color Quahog will give you a blue
color so they will be talk about reasons
so different metals they give different
colors in the business what we do in the
be test we take this platinum vehicle as
an unreactive right and then we take
some borax and we heat this then you
heat this water molecule cools off right
and it becomes any to be water right
when you further hit this it solidifies
into glass like shape this one and this
guy when it reacts with the various
vendors is that we go through this guy
when it reacts now I mean gives
different colors in the oxidizing and
reducing flame so this guy if you see
this part is the oxidizing flame then
this lower part is a reducing flame so
this color dye board oxidizing flame
actually so what happens is we have got
to be two or three this is my
transparent react if the whole thing is
all transfer and beam but concerned more
about this part now this is my
transparent beat down right now when I
mix this with some element and when I
heat this it gives different color let's
see some examples
let me finish this part now so if you
see right these transition metals both
of the transition metals actually or not
all the metal through the transition
metals they have sufficient colors in
samurai tone Cove and gives blue
chromium and copper be green and
magnesium indica gives Brown in the
oxidizing flame is of oxidizing flames
gives these colors right and these are
used to identify them in the lab and the
state test is called borax details the
Platinum wire in this we first I will go
right so you need this water is gone and
then any further read you get this B
this is called
actually and then this bead this bead
you add some metals which you want to
test you have to identify the metals and
then I mean heat in the oxidizing flame
you get different colors and I mean that
you can find for example one example is
given is this borax we'd be Shea apart
you add some co bond in this boom right
and then when you heat this the
oxidizing flame you'll get what Kivar
gives what blue color so the reaction
will be like this come on I have this
one but I have the details get see right
this cobalt bit about it and this is
blue color these are I am talking Borden
oxidizing flame example nickel if you
see and I owe you add this b2o3 this
little bit about it this is drawn up
similarly for manganese alight the
reaction here for manganese you eat the
same thing with me clearly but it's mnb
or - OH - and this is manganese
metaphoric this is Marika
similarly chromium will give chromium
metaphoric CR b or two and copper will
give copper bit about it and these guys
have different color and these will give
you the oxidizing flame all right
similarly the reducing flame it will
give a different example copper in the
reducing flame then give a quarter green
curve sorry so with this I mean the
logic here is not to tell you their
colors and all you should not understand
the color or remember the color the
logic here is that the borax gives
different colors for different
transition metals in the we test right
and and this differs in the oxidizing in
reducing flame so if you see this part
is authorized
dispositor do you think playing for the
plate so if you heat somewhere here this
is the reducing plane is agreed
somewhere heads off the better claim so
did this we are able to identify
differently this is the use of black
said because the borax gives a
blacksmith and this beats give different
colors to different Amish limited and
it's helped identify different please
note the Platinum wire is used here
because this is the unreacted so let's
talk about the use of borax the first
this is for the soul ring of metals is
used you must have seen those electronic
circuits they are soldered and they are
soldered using borax so the glass Paris
glass because the heat resistance borax
is used so the barracks beat this we do
justice first it is used it is also used
while in handle industry and is used in
the laundry laundry it is used borax
it is also used to create other parts
there are some of the use of borax thank
you
visit exam viacom to watch free
education videos try 3 on my tests get
the best quality study materials from
the best tutors and mentors and
matchbook thanks and screen