Do subscribe to Ekeeda  Channel and press
bell icon to get updates about latest
engineering HSC and IIT JEE main and
advanced videos Hello Friends  now we are going
to talk about  the property that we are observing in the  
electron beam enthalpy than that of
cooling so this is what we are going to
discuss about the trend that we have
learned in our previous lecture that we
have got to know that the electronegavity
enthalpy decreases down the group and
increases across the period so let us
talk about that with the help of the
sphere
so now we are going to discuss it that
white chlorine has a less electron gain
and something that that was moving so
before that let me tell you that when it
comes to or the hallux like fluorine
chlorine bromine and a green and phloem
is the first one when it comes to be a
family of elephants so protein comes
first then it comes chlorine and then
Ruby and ivory so this is what we are
going to talk about the group because
this is what we have already discussed
the trend of the electron gained and
happy maybe a can be as specified in
groups and we had also a section where
we have discussed and what would be
their trend in period so not because
what we had echo should we have a
portion of fluorine and chlorine and
then we have belonging in the same group
then citizen will take the help of the
previous lecture that we have studied in
that we have studied that as you move
from up to down
that is a down the blue we could see
that the atomic number goes on
increasing that if the atomic number
falls on increasing and more than what
we could see that the atomic size goes
on increasing and if the atomic size
goes on increasing that will lead to the
decrease in the nuclear charge and
because of the decrease in the debaters
what we could observe is that the
electron gain and help even also
decrease so in this case basically when
we are talking about fluid and chlorine
so what usually it should happen it
should happen that the fluid should have
less size which is compared to that of
the blowing we should have a bigger size
and moreover we could see that the
nuclear charge will be therefore more
when it comes to flowing and then the
temperatures will be unless when it
comes to learning but what will be the
influence what had made the flow into
the less electronegative less electro
what made the flowing it to have less
negative electron wavelength happy then
that of chlorine so this is what we are
going to discuss on but this is a very
unusual thing that we are going to see
now so let us talk about the reason
behind that
okay hopefully in Philly they can be
represented in this form like electronic
configuration that is 1s2 2s2 2p5 so
this is what the filling can be
represented but then of the Blooey
it could be represented as Coolidge 17
which means it has an atomic number of
17 so we could write this as 1 is to 2
is to
2p6 3s2 and 3p5 so here you could
observe very clearly that the outermost
shell in the fluid is 2 and whatever the
orbital is here to z by the case of the
chlorine it is 3 so how many it comes to
the electron gain enthalpy that means we
are adding the electron in the outermost
shell or anyhow we are adding the
electron in the atom so this case
suppose is whenever we will add the
electron in case of flowing what happens
is the main reason that we have did
earlier we the main reason that we have
did that is the first reason that is the
flowing hair will have less atomic size
than that of the chlorine so this is the
most important reason that we are good
talkable so because the fluid has less
atomic size compared to that of the
bluing and that makes employees who have
more density of the electrons because it
is small volume it acquires more
electrons or you could say their 9
electrons having a quite a bit small
size so that means the density of the
turn to be more engaged or flowing by in
case of Chloe chlorine has something
which has more number of shion's
compared to that of moody heat flowing
which makes the density not like more
than that of these fluorine so this
includes what this improves that
whenever we will add an electron to flow
in and because the fluorine has less
atomic size and moreover we could see
that this 2p the electron will be added
in the 2p v
orbital as you could see so the electron
man it will add in the 2p orbital it
will face no
repulsion so because of it will face
more repulsion because the electron
density is more in case of slowly so
because of which there will be no high
negative charge high negative be a
permanent help even talking about
fluorine but in case of gluing it for me
a normal one because the electron make
me add up with the chlorine and the
change in enthalpy for the electron
unions will be it will be more negative
compared to that of the flu so let me
give you a short idea that what we have
got to know we have to go that then
flowing which is in against the state
suppose if an electron is been added up
in that atom which has a lower size as
well as we have seen there the densities
removed so because of the increase in
density of the negative charge of the
negative electrons and if we add more
and I come to that so therefore it will
phase repulsion so because of this
repulsion the it will it will eventually
do form f- but the change in enthalpy
that people to observe even the electron
in enthalpy that we are talking about so
in that case in force be informed to be
that is minus three to eight kilo joule
per mole
while talking about Chloe
so Chloe which is a gases atom suppose
empty in that case if we have added an
electron so as to make a negative charge
I am in this case you could observe so
in this case the electron beam enthalpy
that we that was we measured it was
found to be basically minus three over
nine kilo Joule per mole but in extra
practice what it should have a
particularly that this ring that is the
first member of the growth should have
the higher negative values so in this
case it is literally missing that is 3
into 8 is less that means lesson in the
sense and less of negative than the head
of minus 3 for neck so this makes that
the energy released when electron is
been accepted by an atom in this case it
will be less will be the energy released
when the electron is connection rather
chlorine it will be in this case with
people
so they're here the magnitude is more
and here the magnitude is less but this
is not the usual fact when we have
learned the electron beam ends up with
the trend in electron beam and that
means we are going to know that when we
move from up to down or down the roof
what we observe is is the electron gain
and decreases means it will become less
negative but in this case what happens
is it happens to be quite inverse that
is it will become less negative
while this already become more negative
so because of the reason that we have
got to know that flowing has less air
from a and not B because of its density
of electrons and because of the
repulsion of the electrons that will
help in the 2p orbital so that makes a
reason then the fluorine will have less
electron beam and then good so thank you
thanks for watching this video I hope
you have liked this video maybe we have
understood this concept very clearly and
we guess we have got through an unusual
path so share this video with your
friends and yes don't forget suscribe
Jana thank you so much
