Trends in Group -16 Elements (part - 1) Video Lecture - NEET

hello friends this video on P block
elements part 25 is brought to you by
exam fear calm no more fear from exam so
that's all about the occurrence let's
start with the trends of the elements in
the group 16 so we will discuss about
the electronic configuration plans
density melting point boiling point
atomic and ionic radii ionization
enthalpy electronegativity metallic
character oxidizing and reducing agent
oxidation states nature of compounds and
chemical properties let's start with the
electronic configuration they all group
16 elements and they have the electronic
configuration of n s 2 and P 4 2 plus 4
is 6 and plus 10 gives the group number
that is group 16 elements if we talk
about oxygen atomic number 8 electronic
configuration is 1s2 2s2 be 4 so this is
my format n is 2 and before we talk
about sulphur atomic number is 16 the
electronic configuration is you take the
electronic application neon 3s2 3p4
similarly for selenium you see for s2 4
p 4 for tellurium it is 5 s 2 5 p4 4
perón IAM it is 6 s to 6 people so all
these are following the same standard
the next is the atomic and ionic radii
as we go down the groove the size
increase this is a very common trend in
almost all the routes you go down the
size increase why because the number of
shells are increasing the size increase
if you talk about the size of oxygen it
is exceptionally small so oxygen is very
very small so you see the size of oxygen
is 66 if you talk about a covalent
radius from 66 to 1 0 4 almost 50
person increase or even more than that
yeah 50 percent is 33 almost 60 percent
I get sixty percent increase in size but
from here to here it's 10 percent this
officer is almost 12% 15% and the rise
and here to here is not even 10% maybe
he's expression so but you see oxygen
and sulfur is a 60% increase in size so
oxygen is very very small as compared to
other elements you see almost half
correct and that is why oxygen is very
special oxygen the size is very small
and also we talked about the
electronegativity it is very high and
and that's why oxygen shows some special
properties we'll talk about right right
the next is my density so talk about
density density also if we go down the
group density increase density is what
mass by volume the volume is increasing
but the mass is increasing at a higher
rate right
so mass increase mass increase at higher
rate so we see from 8 to 16 double right
16:24 again double 34 to 52 almost 70
was increase but in this the increase in
the volume was we have seen this was 60
percent this was almost 10 percent this
was almost I think 12 13 % of 15 percent
but if you see the English this is my
increase in volume Delta V but if you
see increase in mass Delta M this is
almost double hundred percent this is 16
to 34 both and double 120 percent levy
or 110 question and this is again the
huge increase maybe 81 if you see
increase in mass is very high
hundred-person 100 bucks 100 or 80
percent but increase in volume is less
so density is mass by volume this
is less this increases more so the
numerator is increasing at a higher
speed than denominator does the overall
density will also increase and that's
what we see the density is also
increasing as we code on the crew okay
let's talk about the melting point and
the boiling point see the melting point
and boiling point if you see oxygen the
melting point is what 55 from oxygen and
sulfur there is a huge increase in the
melting point okay what and also if you
see notice here the melting point and
boiling point also has a huge difference
the reason why this is a huge increase
in the melting point on boiling point of
again say here is see oxygen is diatomic
and sulfur is off title es8 correct now
to boil it or to actually melt this you
have to break this bonds since sulfur as
a kind of structure it is actually the
blue weight of structure see this kind
of structure this is the kind of
structure of sulfur oxygen it is a
diatomic it is more difficult to break
this bond so many bonds have to break
okay thus the boiling point of sulfur is
very high think these are all exist as
polyatomic they all exist as
polyethylene
but sul oxygen exist as diatomic the
huge different oxygen and sulfur as far
as the boiling point is concerned okay
let's see the ionization enthalpy so if
you see you go down the group the
ionization enthalpy decrease why because
there's an increase in size
okay so ionization enthalpy is again
amount of energy required to clock one
letter correct to pluck one electron so
if the size increase it is easier to
pluck electron because this electron
will not be much controlled from this
nucleus but the size is dick small this
electron is tightly controlled by this
nucleus you have seen this concepts
actually okay
and typically the group 16 this is group
16 elements it has lower ionization
enthalpy as compared to group 15 to 15
this I evaluate hi why any guess see
group 15 we have seen that they have
half-filled p orbital their electronic
confusion was NS 2 n p3 this half-filled
p orbital gives extra stability to rule
15 since they are stable they don't want
to lose electron and with that concept
they did more higher they you need more
energy to pluck one electron from group
15 elements then you need to pick one
electron from the group 16 isn't it why
because the group 15 is half stable or a
half-filled extra stability they don't
want to lose electron right to two
trends in ionization therapy one is very
good on the group - enthalpy decrease
very simple reason is that
sighs increase it's easy to pluck
electron but when you compare group 15
in group 16 that is my group 15 element
will have a higher ionization enthalpy
then group 16 elements why because they
are extra stable because of half and P
already the next is the
electronegativity electronegativity also
if you see it decreases as we go down
the group the reason can be young
increase in size the increase in size
these atoms are not able to attract
electrons towards itself right so
tendency boxed-in to attract electron to
what itself is maximum in this group and
thus oxygen is the most electronegative
element in the tube 16 okay the next
thank you visit exam viacom to watch
more videos at M free online test get
three study materials find tutors and
mentors and much more thanks once again