Periodic Table

Periodic Table

Name : Nurwajiha Humaira bt.
Noraini

Matric No. : MS2117119527

Tutorial Class : M3T15

Lecturer’s Name : MUHAMAD AZRANI BIN
ZAMERAHIM

Introduction

1 The elements in the periodic table are arranged in ascending
order to proton number.

2 The elements that I have been choosen is Magnesium, Sodium,
Aluminium, Potassium and Chlorine.

The reason why I choose Sodium and Potassium is because

3 they are in the same group which is group 1 . They can be used
to show variation of atomic radius, ionic radius, IE and
electronegativity.So, they are easy to be compared down the
group.

4 I choose Magnesium and Aluminium is because these elements
are easy to be compared in anomalous case.

5 The reason why I choose Chlorin is because it is located at the
same period with Magnesium and Aluminium which is period
3. Thus, they can be used to show variation of atomic radius,
ionic radius, IE and electronegativity across the period

Elements

ELEMENTS IN GROUP

Elements Mg Na K Al Cl

Electronic 1s2 2s2 2p6 1s2 2s2 2p6 1s2 2s2 2p6 1s2 2s2 2p6 1s2 2s2 2p6
Configuration 3s2 3s1 3s2 3p6 4s1 3s2 3p1 3s2 3p5
2 1 3 7
Valence 1
electron 2 1 13 17
1
Group

Period 3 3 4 3 3

Block s s s p p

ELEMENTS IN GROUP

Elements Group Explaination
Magnesium, Mg 2
Sodium, Na 1 Magnesium is located in s-block. It has 2 valence
Potassium, K 1 electron in 3s orbital. Hence, it is located at group 2.
Aluminium, Al 13
Sodium is located in s-block. It has 1 valence electron in
Chlorine, Cl 17 3s orbital. So, it is located at group 1

Potassium is located at s-block. It has 1 valence electron
in 4s orbital. Thus, it is located at group 1.

Aluminium is located at p-block. It has 3 valence
electron in 3s and 3p orbital. So, it is located at group
13

Chlorine is located at p-block. It have 7 valence electron
in 3s and 3p orbital. Thus, it is located at group 17

If the element is located p-block, the number of group can be
determined by the formula - (number of electrons + 10 )

It is shown that Sodium, Na and Potassium, K is located in the same group which is
group 1 because they have same number of valence electron which is 1

ELEMENTS IN PERIOD

Elements Mg Na K Al Cl

Electronic 1s2 2s2 2p6 1s2 2s2 2p6 1s2 2s2 2p6 1s2 2s2 2p6 1s2 2s2 2p6
Configuration 3s2 3s1 3s2 3p6 4s1 3s2 3p1 3s2 3p5
2 1 3 7
Valence 1
electron 3 3 3 3
4
Principal 3 3 3 3
quantum 4
number, n

Period

Block s s s p p

ELEMENTS IN PERIOD

Elements Period Explaination
Magnesium, Mg 3
Sodium, Na 3 The principle number of valence electron in Magnesium
Potassium, K 4 is 3 . So it is located in period 3
Aluminium, Al 3
Chlorine, Cl 3 The principle number of valence electron in Sodium is
3. So it is located in period 3

The principle number of valence electron in Potassium
is 4. So it is located in period 4

The principle quantum number of valence elecron in
Aluminium is 3. So it located in period 3

The principle quantum number of valence electron in
Chlorine is 3. So it located in period 3

Hence, Magnesium, Sodium, Aluminium and Chlorin located at the same
period because they have the same number of principal quantum number of

valence electron

Atomic Radius

❖ The atomic radius is taken as half of the distance between the nuclei of two adjacent

identical atom

❖ The size/ raidus of atom is difficult to be defined because the electron cloud has no

clear boundary.

FACTORS OF ATOMIC RADIUS:

✓ Effective nuclear charge

- “positive charge” felt by an electron

Zeff = Z-S Z= no. of proton
S = no. of electron filled at the inner shells

✓ Screening effect

- caused by the mutul repulsion between the inner shell electrons and the outer shell

electrons

DOWN THE GROUP Comparison between Sodium, Na and Comparison between Magnesium, Mg and
Potassium,K Chlorine, Cl

➢ These atoms are located at the same group ➢ These atoms are located at the same period
which is Group 1 which is period 3.

➢ The principal quantum number ,n of valence ➢ Proton number of Cl Z=17 is higher than Mg
electron in potassium atom is n = 4 is larger Z=12.
than potassium atom n= 3.
➢ Effective nuclear charge of Cl atom is higher
➢ Potassium atom, K has more number of inner than Mg atom
electrons and inner shell compared to sodium
atom, Na ➢ Valence electron of Cl atom is pulled closer to
the nucleus compared to Na atom.
➢ Sreening effect in potassium atom, K is higher
than sodium atom, Na because the inner ➢ Nucleus attraction of Cl become greater than
electrons shield the outer electron of atom. Mg.

➢ Valence electrons attracted weaker in So, atomic radius of Cl atom is bigger than Mg
Potassium atom , K compared to sodium atom
atom, Na
ACROSS PERIOD
➢ The distance between nucleus and valence
electron in K is larger compared to Na.

So, atomic radius of K is bigger than Na

Atomic radius =
Cl, Al, Mg, Na, K

ascending order

Electronegativity

• tendency of an atom to attract electrons (or electron density) of covalent bond towards itself.
• Atoms with strong attraction of the nucleus and the outer electron have the high

electronegativity

Comparison between Sodium, Na and Potassium, K Comparison between Aluminium, Al and Chlorine, Cl

D ➢ The principle quantum number of K atom (n=4) is ➢ Number of proton in Cl atom (Z=17) is higher than
Al atom (Z= 13)
O higher than Na atom (n=3)
W ➢ Number of shells in K atom is higher and the ➢ Attraction between nucleus and valence electron
in Cl atom is greater than Al atom.
N atomic size is bigger compared to Na
T ➢ Shielding effect of K atom is greater than Na atom ➢ Atomic radius of Cl atom is larger than Al atom.
H ➢ Attraction between nucleus and valence electron ➢ Tendency of Cl atom to attract electron to itself is

E in K atom is weaker than Na atom greater than Al atom
G ➢ Tendency of K atom to attract electron to itself is ➢ Thus, Cl atom has higher electronegativity

R small compared to Na atom compared to Al atom
O ➢ Thus, K atom has less electronegativity compared
➢ Electronegativity increases across the period
U to Na atom.

P
➢ Electronegativity is decreases down the group.

ACROSS THE PERIOD

K,Na,Mg,Al,Cl

ascending order

Ionisation Energy

❖ Minimum energy required to remove an electron from a gaseous atom or ion in its ground state.

Comparison between Natrium, Na and Chlorine, Cl Comparison between Natrium, Na and Potassium,K

➢ The size of Cl atom is smaller than Na atom because ➢ Number of shells in K atom (n=4) is greater than

the effective nuclear charge increase across the Na atom (n=3) D

period. ➢ The shielding effect in K atom is greater than Na O

➢ The distance of valence electron in Cl atom is closer to atom W

the nucleus compared to Na atom. ➢ Atomic radius of K atom is bigger than Na atom N

➢ Atomic radius of Cl atom is smaller than Na atom ➢ The distance of valence electron in K atom is far

➢ Thus, the attraction between the nucleus and valence away from the nucleus compared to Na atom. A

electron in Cl atom is greater than Na atom. ➢ Thus, attraction between the nucleus and the

➢ Cl atom is difficult to remove an electrons from each valence electron in K atom is weaker than Na G

atom compared to Na atom atom. R

➢ Energy needed to remove the outermost electron in ➢ So, the energy needed to remove first electron in O

Cl atom is higher than Na atom. K atom is less compared to Na atom. U

➢ Hence, the ionisation energy of Cl atom is greater ➢ The ionisation energy of K is lower than Na atom. P

than Na atom ➢ IE DECREASE down a group

➢ IE INCREASE from left to right across period.

ACROSS PERIOD

K,Na,Mg,Al,Cl

ascending order

Ionisation Energy

Mg -----> Mg+ + e- FULL FILLED 3S ORBITAL
1S2 2S2 SP6 3S2 -----> 1s2 2s2 2p6
3s1 PARTIALLY FILLED
3P ORBITAL
Al -----> Al+ + e-
1s2 2s2 2p6 3s2 3p1 ------> 1s2 2s2
2p6 3s1

In Al atom, the attraction between nucleus towards 3p electron is weaker
Less energy needed to remove a single 3p electron in Al compared to paired electron in Mg atom
In Mg atom, the s orbital are full-filled and this conferred more stability on the electron.
Hence, more ionisation energy ( IE ) will be required to remove one of them
So, the ionisation energy of Mg atom is higher than Al atom.

Mg2+ = 1s2 2s2 2p6
Na+ = 1s2 2s2 2p6
K+ = 1s2 2s2 2p6 3s2 3p6
Al3+ = 1s2 2s2 2p6
Cl- = 1s2 2s2 2p6 3s2 3p6

• across period, size • ionic radii increase
from K+ to Cl-
of cations and
• They are
anions decrease due
isoelectronic
to the increase of
because their
proton number
• Ionic radii of Na+> electronic
configuration is 1s2
Mg2+>Al3+ 2s2 2p6 3s2 3p6
• They are • Proton number and

isoelectronic effective nuclear

because their charge, Zeff
decreases from K+ to
electronic Cl-
configuration is 1s2
2s2 2p6

Ionic radius of Na+ Al3+ and Cl-

➢ Ionic radii of cations decrease from Na+ to Al3+
➢ The proton number and the effective nuclear charge, Zeff increase from Na+ to Cl-
➢ The ionic radii decrease from Na+ to Al3+
➢ But, the ionic radii increase from Al3+ to Cl-
➢ Cl- adding on 1 electron at the outer shell
➢ The screening effect is increase hence, the ionic radii increase from Al3+ to Cl-

CROSS WORD
CROSS WORD



ACROSS DOWN

2) elemntary particle with zero charge 1) capable of being shaped or bent or
4) a stable particle with positive charge drawn out
5) a mixture containing two or more 3) the positively charged dense centre of an
metallic elements atom
6) any of the chemically inert gaseous 5) the smallest component of an element
elements of the helium group in the 7) any of the monovalent metals of group1
periodic table of the periodic table
8) a chemical element that is usually a shiny 9)the order of an element i the periodic
solid table of elements
12) atom with same atomic number, 10) ready susceptinility to chemical change
different number of neutrons 11) representation of something, often a
14)arrangement of chemical according to smaller scale
atomic number 16) an elementary particle with negative
15) the transmission of heat or electricity or charge
sound
17) capable of being shaped or bent
18) deterioration in metals from oxidation
or chmical action
19) the sum of the number of neutrons and
protons in an atomic nucleus

CONCLUSION

One of the most significant achievements in the science of chemistry
is the periodic table. It's full with patterns that help us comprehend the
world around us better. The knowledge gathered from the periodic
table can open up a plethora of windows into the cosmos we live in. I
could gain a much better grasp of the periodic table as a result of this
assignment. Now, I have a much better understanding of the periodic
table and its components including the basic atomic structure of the
elements that make up the periodic table.

I have seen the trend of the periodic table in period and group,
atomic radius, ionic radius, ionisation energy and also electronegativity.

References

1. Periodic Trends- Ionization Energy. (2021, June 20). Retrieved September 26, 2021, from
https://chem.libretexts.org/@go/page/5370

2. Nelson, D. (2020, March 15). Electronegativity Trend. Science Trends.
https://sciencetrends.com/electronegativity-trend/

4. Libretexts. (2020a, August 15). Atomic and Ionic Radius. Chemistry LibreTexts.
https://chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemistry_Textbook_Maps/Suppleme
ntal_Modules_(Physical_and_Theoretical_Chemistry)/Physical_Properties_of_Matter/Atomic_and_Molec
ular_Properties/Atomic_and_Ionic_Radius

5. Anomalous trends in ionization energy. (2015, June 2). Chemistry Stack Exchange.
https://chemistry.stackexchange.com/questions/32363/anomalous-trends-in-ionization-energy

6. E-book
Bewick, S., Parsons, R., Forsythe, T., Robinson, S., & Dupon, J. (2021, March 5). Introductory Chemistry
(CK-12) [E-book].