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periodic table

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AM
IN
Periodic Table
+1 +2
8
+3 -+4
2
3
2
3
4
5
6
0
4
5
6
7
SA
DI
Q
7
https://ptable.com/#Properties
Periodic law
Properties of the elements of the periodic
function of their increasing atomic number .
Mr
Mr.Sadiq Amin
-1
8/0
1
1
-3_ -2
or
AM
IN
elements are arranged in the periodic table
on the basis of increasing atomic number .
There are groups and periods in the periodic
table .
groups are the vertical columns of elements
in the periodic table .
Q
periods are the horizontal rows of elements
in the periodic table .
DI
There are seven PERIODS in the periodic
table.
SA
and there are 18 groups in the periodic
table .
group number one is called the alkali metals
where highly reactive metals .
Mr
group #2 is called alkaline earth metals they
are less reactive than alkali metals .
in the middle of the periodic table there are
transition metals .
AM
IN
on the right side of the periodic table
mostly from group #13 to group #18 are
nonmetals.
Group #13 is called boron family .
group #14 is called carbon family
Q
group #15 is called nitrogen family
group #16 is called oxygen family
DI
group #17 is called the halogen family
SA
group #18 is called the Noble gases .
Mr
WE will Work on the electronic
configuration of the elements starting from
hydrogen which is element NO#1 in the
periodic table ,and ending up on calcium
which is the 20th element of the periodic
table .
AM
IN
what is the atomic number ?
that is the number of protons in an element
,periodic table is arranged on the basis of
increasing atomic number .
what is atomic mass ?
the total number of protons and neutrons
in the nucleus of an element .
2He
SA
1H
DI
Q
protons and neutrons are in the centre of
an element (Atom ),and electrons are
revolving around the nucleus (centre the
Atom ).
Mr
5B
6C
3Li
7N
4Be
8O
13Al
15P
14Si
17Cl
Mr
SA
18Ar
DI
Q
16S
AM
IN
12Mg
19K
Those elements which are in the same
group they have the same outer most
20Ca
AM
IN
electronic configuration will take the
example of group number one lithium
sodium and potassium and will cheque the
electronic configuration of the outer most
shell .
Q
GROUP NO 1.
11Na
19K
DI
3Li
SA
GROUP NO 2.These elements have two
electrons in their outer most shell (the last
shell )
Mr
4Be
12Mg
20Ca
AM
IN
NOTE:The electrons in the outer most shell
are showing the group number .
and the total number of shells are telling us
about the period number .
period no# 3 = 3
Q
Example.
group no# 5= outer electrons
first shell =2
SA
middle=8
DI
the element is phosphorus
last shell=5
total electron=15
Mr
PERIODIC TABLE LINK
https://ptable.com/#Properties
AM
IN
There are two types of elements in the
periodic table .
SA
DI
Q
1. the metals (mostly on the left side of
the periodic table )
2. the nonmetals (mostly on the right
side of the periodic table )
3. Metalloids those elements of the
periodic table which are having both
the properties of metals and
nonmetals .
2n2 Is used to fill the electrons in the
shells ,where n stands for the number
of shell ,(shell NO# 1,2,3,4,5,6,7)
ELECTRONS IN THE SHELLS USING THE
FORMULA 2n2
Formula Total electrons
Mr
2(n)2
Shell Shell Shell Shell NO4
NO1 NO2 NO3
2(1)2=2x(1x1)=2
2
2(2)2=2x(2x2)=8
8
2(3)2=2x(3x3)=18
18
2(4)2=2x(4x4)=32
2x(4x4)=32
AM
IN
SA
DI
Q
Properties of metals and nonmetals
S.no Metals
Non Metals
1
Ductile
Non Ductile
2
Malleable Non Malleable
3
Sonorous Non Sonorous
4
NonBrittle Brittle
5
Conductors Non conductors
except graphite
6
Shiny
non shiny /Dull
7
High
Low density
density
8
high
low melting and
melting
boiling points
and boiling
point
Mr
Ductile: to be drawn out into a thin wire
Malleable: That can be hammered into
sheets .
DI
Q
AM
IN
Sonorous :Having ringing sound .
Brittle: it means can be shattered into
pieces .
Q. Group 0 Noble gases are non reactive
/inert ,why they don't react ?
Ans: because their outer most shells are
having complete electronic configuration
,that's why they don't react at all .The
complete electronic configuration should be
2/8/18/32.
NEXT TOPIC
Acidic and basic characters of the oxides of
metals and nonmetals
SA
Oxides are the binary(only made of
Mr
two elements ) compounds of oxygen with
other elements.
There are SEVEN types of oxides .
4 of the oxides are the part of our course .
1. acidic oxides
2. basic oxides
neutral oxides
amphoteric oxides
sub oxides
PER oxides
superoxides
Acidic Oxides .
AM
IN
3.
4.
5.
6.
7.
Q
These are the binary compounds of oxygen
with nonmetals .
their solutions are acidic in nature .
DI
they turn blue litmus paper red
Their pH is less than 7 .
SA
examples are .
CO2,NO2,SO2,SO3
These oxide produce acidic solution and dissolved in water .
CO2+H2O→H2CO3 (CARBONIC ACID)
2. NO2+H2O→HNO3 (NITRIC ACID)
3. SO2+H2O→H2SO3 (SULPHUROUS ACID)
4. SO3+H2O→H2SO4 (SULPHURIC ACID)
Mr
1.
AM
IN
BASIC OXIDES.
These are the binary compounds of oxygen
with metals .
they are alkaline in nature .
they change red litmus paper blue .
their Ph is more than 7 .
the examples are.
Q
Na2O,MgO,CaO,K2O
SA
DI
Reactions of metal oxides with water will
always make an alkaline solution ,the pH
will be more than 7 and it will be turning
blue litmus paper to red .
1. Na2O + H2O→ NaOH (sodium hydroxide)
2. MgO + H2O→ Mg(OH)2(magnesium hydroxide )
3. CaO + H2O→ Ca(OH)2(calcium hydroxide )
Mr
4. K2O + H2O→ KOH (potassium hydroxide)
Neutral oxides .
AM
IN
these are also the binary compounds of
oxygen with other elements .
they don't change the colour of the litmus
paper .
their pH is at 7 exactly .
Examples are :water(H2O) ,carbon
monoxide(CO) ,nitrogen monoxide (NO).
Q
Amphoteric oxides :
DI
these oxides are having dual properties
,when they reacted with acids they behave
like alkalies,And when they reacted with
alkalies,they behave like acids.
SA
examples are .
Mr
ZnO,Al2O3,PbO.
Next
AM
IN
Chemical reaction of amphoteric oxides
•
Reaction with an acid
ZnO(s) + 2HCl(aq) → ZnCl2(aq) + H2O(l)
Reaction with a alkali
ZnO(s) + 2NaOH(a) → Na2ZnO2(aq) + H2O(l)
•
Reaction with an acid
Al2O3(s) + 6HCl(aq) → 2AlCl3(aq) + 3H2O(l)
•
Reaction with a alkali
Al2O3(s) + 2NaOH(aq) → 2NaAlO2(aq) + H2O(l)
•
Q. Why elements in the same group have
Similar chemical properties ?
DI
Q
Ans: Because they have the same number
of valence electron in their outer most
shell .
SA
Q.Why metals are good conductors of
electricity?
Ans: Because they are having delocalised
mobile electrons which are responsible for
the conductance of electricity .
Mr
Properties of Group One elements
Group One elements are also called alkali metals .
AM
IN
okay this start with lithium ,sodium ,potassium
,Rubidium ,caesium ,francium
1.All the elements in Group one react violently with
water, releases hydrogen immediately,which catches
fire .the reaction with air is also very fast their freshly
cut surface is are shiny but they get dull very quickly .
Group1 reaction with water.
Group One elements are highly vigorous while reacting with
with cold water ,The rate of reaction is increasing down the
group and we can see some intensifying chemical reactions .
2K + 2H2O→ 2KOH + H2
Q
2Na + 2H2O→ 2NaOH + H2
DI
The reactivity of Group One elements increases down
the group ,so we can say that francium is more
reactive than lithium .
SA
The highly reactive metals are at the bottom and the
low reactive metals are at the top of the group .
Physical properties
Mr
1. They are soft metals ,can be easily cut with knife .
2. their freshly cut surfaces are shiny ,and get dull
quickly reacting with oxygen in the air .
3. as they are highly reactive so they are kept under
kerosene oil for safety.
4. They have only one electron in their outer most
shell.
AM
IN
5. they make positively charged ions Na1+
6. they react with group 7 elements to make ionic
salt's
7. These elements are not freely(It means elemental
form original form ) available ,they are extracted
from compounds by electrolysis method .
8. their solutions are alkaline it means they have a
pH above 7 .
Properties of group 7 elements .
Mr
SA
DI
Q
1. group7 elements are called halogens(salt
making).
2. They all have 7 electrons in their outer most shell.
3. they have a charge of minus one on the negative
ions .
4. their names are ,flourine ,chlorine ,bromine ,
iodine, Astatine.
5. The first 2 elements of this group fluorine and
chlorine are in the gaseous state ,bromine is in
the liquid state ,iodine and astatine are in the
solid state.
6. Colours of group 7 halogens .
i. florine yellow
ii. chlorine yellowish green/greenish yellow
iii. Bromine Brown.
iv. Iodine grey
astatine black
AM
IN
v.
Chemical reactions of halogens .
there are 3 types of reactions of the halogens .
a. Reaction with hydrogen
F2 + H2 → 2HF
→ This reaction happens in darkness it doesn't need
any energy .vigorous reaction
Cl2 + H2→ 2HCl
Q
→ this reaction needs a little bit of energy but still it's
vigorous enough
DI
Br2 + H2→2HBr
→this reaction needs more energy a little heat can
initiate the reaction is vigorous
I2 + H2→ 2HI
SA
→more heat energy is required to start this reaction
but once it's started it's vigorous as well .
They are all diatomic in nature.
Mr
The reactivity of the halogens decreases down the
group ,the highly reactive elements are at the top
unlike Group One elements where the highly reactive
are at the bottom .
AM
IN
Q. Working with bromine water in the laboratory ,if
there's a spillage of bromine water on the table ,how
will you clean it ?
Ans:if there's a spillage of bromine water on the table
in the laboratory ,we will use
sodiumthiosulphate(Na2S2O4)to neutralise the effects
of bromine water ,only this chemical can neutralise its
poisonous effects.
b. reactions with alkali metals.
Q
These reactions are also vigorous in nature ,very
explosive sort of reactions can be seen .
SA
DI
if we take molten sodium in the gas jar of chlorine
,we will see an explosive reaction ,with orange
colour flame ,releasing a white smoke ,and a huge
amount of heat energy . This will result in making
an ionic salt of sodium chloride .
2Na + Cl2 → 2NaCl
2K + Cl2 → 2KCl
Mr
c. displacement reactions
Displacement reactions are those reactions in
which a highly reactive element displaces the low
reactive element .
fluorine is more powerful than chlorine and the
rest of the elements .
F2>Cl2>Br2>I2
AM
IN
every top element of the group is reactive more
then the bottom element .
If we have a solution of sodium chloride and we
add flourine to it ,it will displace chlorine out of
the solution and takes its place .
2NaCl + F2→ 2NaF+ Cl2
Q
NOTE : Halogens are all poisonous in nature ,they
can only be neutralised with a solution of
sodiumthiosulphate(Na2S2O4) .
Mr
SA
DI
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