C4 TAHAP 2 NORAIDAH
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Transcript of C4 TAHAP 2 NORAIDAH
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4541 CHEMISTRY MODUL P3T (TAHAP 2)
CHAPTER 4 : THE PERIODIC TABLE OF ELEMENTS
A Historical Development Of The Periodic Table
1 Antoine Lavoiser(1743-1794) The first Scientist classifies substances including . and ., into
..and.
Substances were classified into fourgroups with similar chemical properties.
His classification was unsuccessful because , and a few
other compounds were also considered as elements.
2 Johann Dobereiner(1780-1849) Divided the elements into groups of three elements with similar chemical
properties, known as .
The atomic mass of the middle element was approximately the average atomic massof the other two elements in each triad.
This classification led chemist to realise that there was a relationship between the
. and the atomic mass of each element.
Example :
Element in triad Li Na KAverage relativeatomic mass of Li
and K
Relative atomicmass, Ar
7 39 2
397 += 23
3 John Newlands (1837-1898) He arranged the known elements in order ofincreasing atomic mass.
Elements with similar chemical properties were repeated at every eighth element.
This was known as the Law of.
This system was inaccurate because the Law of Octaves was obeyed by the first 17elements only and there were some elements with wrong atomic mass/mass number.
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However, Newlands was the first chemist to show the existence of.for the properties of elements.
4 Lothar Meyer(1830-1895) He plotted a graph of.. against for all theknown elements.
Atomic volume =
He realised that elements with .. occupied equivalentpositions along the curve.
He was successful in showing that the properties of the elements formed a periodic
pattern against their..
5 Dimitri Mendeleev (1834-1907) Arranged the elements in order of ...
He grouped the elements according to ...
[Elements with similar chemical properties were in the same group].
He left gaps in the table to be filled by .. elements.
He was able to predict the properties of undiscovered elements.
[e.g: Ekasilicon, Es is predicted by Mendeleev in 1869 was discovered asGermanium, Ge in 1886 ].
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Mass of 1 mol (g)
Density (g cm-3)
Li
Atomic
volume
Atomic mass
Na
K
Be
Mg
Ca
B
Al
What colourshould be here?
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Hendry J. G. Moseley (1887-1915)
Studied the .. of elements.
[Introduced the concepts ofproton numberof each elements]
He concluded that should be used as the basis for theperiodic changes of chemical properties of elements instead of the atomic mass.
He rearranged the elements in order ofincreasing proton numberin the PeriodicTable.
B Arrangement of Elements in the Periodic Table
Elements in the Periodic Table are arranged in an .. order of
.., ranging from 1 to 112.
Elements with .. are placed in the same vertical column called
..
Lanthanides
Actinides
There are vertical columns of elements in the Periodic Table.
Each vertical column of elements is called a ..
The vertical columns are known as to .
There are horizontal rows of elements in the Periodic Table.
Each of these horizontal rows of elements is called a
The horizontal rows are known as . to.
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Horizontal row
Verticalcolumn
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Activity1:-
In the table below, write :
(a) Group 1 to 18(b) Period number 1 to 7
(c) the symbol of each element from Hydrogen to Calcium
H He
Lanthanides
Actinides
The number ofvalence electrons in an atom decides the .. of anelement in the Periodic Table.
Example :
The proton number of sodium, Na is 11.The electron arrangement of sodium atom is 2.8.1The valence electron of sodium is 1Sodium is placed in Group 1 in a Periodic Table.
For elements with 1 and 2 valence electrons, the group numberof the element is thenumber of valence electrons in its atom.
For elements with 3 to 8 valence electrons, the group numberof the element is the
number of valence electrons in its atom plus ten (+10) [ valence electron + 10 ]
Example :
The proton number of chlorine is 17The electron arrangement of chlorine is 2.8.7The valence electrons of chlorine is 7Chlorine is placed in Group 17 [ 7 +10 ]
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Elements from Period 3
Complete the following table.
The position in theperiodof an
element in the
Periodic Table is
determined by the
number of
..
occupied/filled with
electrons in the atom
of that element.
Theperiod numberof an element is the number of shell occupied with electrons in itsatom.
Example :
The proton number of magnesium is 12The electron arrangement of magnesium is 2.8.2There are 3 shells occupied with electrons in magnesium atom.Theperiodnumber of magnesium in the Period Table is 3
Activity2:-Complete the following table :
Element Li C O Ne Mg Al P Cl K Ca
Proton number 3 6 8 10 12 13 15 17 19 20Electronarrangement
2.1 2.8.2 2.8.3
Number ofvalenceelectron
3
Group 13
Number ofshellsoccupied with
electrons
3
JPNT 2009 CHAPTER 4: PERIODIC TABLE OF ELEMENTS
ElementProtonnumber
Electronarrangement
Valenceelectron
Group
Na 11 2.8.1 1 1
Mg 12
Al 13 2.8.3 3 13
Si 14
P 15S 16
Cl 17 2.8.7 7 17
Ar 18
42
Group :
Valence electrons + 10
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Period 3
Specific name of certain groups :
Group Specific name
1 Alkali metal #
2 Alkali-earth metal
3 to 12 Transition element #
17 Halogen #
18 Noble gas #
# The important groups that will be studied from the aspect ofphysicaland chemicalproperties.
Activity3:-
1 Write the electron arrangement for each element in the following Periodic Table.
Symbol of element : [ Standard form ]
GROUP
1 18
1H1
.
2 13 14 15 16 17
4 He2
7 Li3
...
9Be4
..
11 B5
12 C6
14 N7
16 O8
19F
9
20 Ne10
23 Na11
..
24 Mg12
.. 3 4 5 6 7 8 910
11
12
27 Al13
28 Si14
31 P15
32 S16
35 Cl17
40 Ar18
39 K19..
40 Ca20..
TRANSITION ELEMENTS
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A
XZ
.number
..number1
2
3
4
PERIOD
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2 Complete the statement and answer the following questions based on the table below.
ElementNucleonnumber Number of neutrons
A 9 4
B 31 16
C 35 18
(i) The proton number of A is and the number of electrons in an atom A is
. .
The electron arrangement of atom A is..
The valence electron of atom A is ..
Atom A is in Group ..and Period ..
(ii) Atom B is in Group ..and Period ..
(iii) A student states that atom C is in Group 17 and Period 3 in Periodic Table of
Element. Is the statement true or false? Explain your answer.
.........
.
.
Advantages of Grouping Elements in the Periodic TableThe systematic arrangement of elements in the Periodic Table helps us to study the
elements systematically, especially in their and .. properties.
Elements with the .. number of . are placed in the same
Group because they have the same chemical properties.Elements are arranged systematically in the Periodic Table in the order ofincreasingproton numberwhich enable chemists to study, understand and remember :
(a) the chemical and physical properties of all the elements and compounds in an orderlymanner.
(b) the properties of elements and their compounds are predicted based on the position ofelements in the Periodic Table.
(c) the relationship between the elements from different groups can be known.
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C GROUP 18 ELEMENTS [Refer to Text Book, page 64]
1. Group 18 elements consists of ., .., .., ,
. and ..
2. These elements are known as gases.
3. Group 18 elements exist as monoatomic at room condition because Noble gases
achived stable electron arrangement which is for helium and
for other elements.
4. Noble gases do not have to lose, gainorshare electrons.
Physical Properties of Group 18 Elements
Noble gases have very .. atomic sizes.
They are . gases at room temperature and pressure.
Noble gases have .. melting and boiling points and also .. densities.
Noble gases are in water, conduct electricity and
. conductors of heat.
Going down Group 18 [Refer to Text Book, page 64]
Element
Relative
atomicmass
Protonnumber
Atomic
radius(nm)
Melting
point(oC)
Boiling
point(oC)
Density(g dm-3)
Helium, He 4 2
Neon, Ne 20 10
Argon, Ar 40 18
Krypton, Kr 84 36
Xenon, Xe 131 54
Radon, Rn 222 86
When going down Group 18 :
The atomic size as the number of shells in the atom increases from Helium
to Radon.
The melting and boiling points is very low.
because the atoms of Noble gases are attracted by weak force.
Less energy is required to overcome it.
However, the melting and boiling points . when going down Group 18.
because the atomic size of each element down the group,
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Increase
s
Increase
s
Increase
s
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the forces of. between the atoms of each element become stronger
thus more is required to the stronger forces of ..
. during melting or boiling.
The density of an element .. down the group because the atomic mass
of each element is
The Inert Property of Group 18 Elements
All Noble gases are inert which means .. .
Noble gases and the electron arrangement of their atoms.
Noble gas Electron arrangement
Helium 2
Neon 2.8Argon 2.8.8
Krypton 2.8.18.8
Xenon 2.8.18.18.8
Radon 2.8.18.32.18.8
Helium has two valence electrons. This is called a . electron arrangement.
Other Noble gases have eight valence electron called the .. electron arrangement.
These electron arrangements are very stable.
That is why Noble gases exist as monoatomicgases and are chemically unreactive;
because they achived the stable octet/duplet electron arrangement.
Uses of Group 18 Elements
Noble gas Uses
Helium, He
Neon, Ne
Argon, Ar
Krypton, Kr
Xenon, Xe
Radon, Rn
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D GROUP 1 ELEMENTS
1. Write the name and symbols of elements in Group 1 (exceptHydrogen)
2. Group 1 are also known as which react with water to form alkalinesolutions.
3. Write the symbols in the boxes for all the elements in Group 1 in the Periodic Table ofElements :
4. Write the proton number and electron arrangement for all elements in Group 1.
ElementsProtonnumber
Electronarrangement
Density /g cm-3
Boilingpoint /
0
CLi 3 0.534 1360
Na 0.971 900
K 0.862 777
Rb 2.8.18.8.1 1.530 505
Cs 2.8.18.18.8.1 1.973
Fr 2.8.18.32.18.8.1
All Group 1 elements have valence electron in their outermost occupiedshells.
5. Physical Properties of Group 1 elements :
metals.
densities.
melting points.
silvery solid with . surface.
good of heat and electricity.
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compared to other metals
such as iron and copper.
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Change in the physical properties going down the group :
The atomic size because the number of shells increases.
The density because the increasing in atomic mass is fasterthan the increasing in atomic volume/size.
The melting and boiling points because when the atomic sizeincreases, the metal bond between the metal atoms becomes weaker.
The hardness of the metal .
6. Chemical Properties of Group 1 elements :
(a) React with waterto produce alkaline metal hydroxide solutions [colourless
solutions] and released gas.
Metal* Observation
Li
Lithium moves .. on water surface with sound.
The solution formed; turns ..litmus paper to...
Na
Sodium moves . on water surface with sound.
The .. solution formed; turns .litmus paper to..
K
Potassium moves . on water surface with .sound.
The . solution formed; turns .litmus paper to..
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water
metal*
Redlitmus paper
turnsblueRedlitmus paper
Reactionbecomes
morevigorous
React
ivityin
creases
Metal G1 + H2O metal hydroxide + Hydrogen gas
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Chemical equation :
# Chemical equation
2Li + 2H2O 2LiOH + H2
Lithium Water Lithium Hydrogen gashydroxide
Write the chemical equation for the sodium and potassium.
..
(b) React with oxygen gas to produce metal oxides [white solids].
Metal* Observations
Li
Lithium burns with a flame.
A . / fume solid is produced.
Na
Sodium burns . with a .. flame.
A .. solid is produced.
K Potassium burns . with a flame.
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Gas jar
Metal*
Oxygen gas
White fume
Gas jar spoon
Reactionbec
omes
morevigorous
Metal G1 + O2 metal oxide
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A solid is produced.
Chemical equation :
Example:
+ O2 2Na2O
4K + O2
(c) React with chlorine gas to produce metal . [white solids].
Elements Observations
Li
Lithium burns with a .. flame.
A . solid is produced.
Na
Sodium burns .. with a flame.A . solid is produced.
K
Potassium burns ... with a ...flame.A solid is produced.
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Gas jar
Metal*
Chlorine gas
White fume
Gas jar spoon
Metal G1 + Cl2 metal chloride
4Li + O2
2Li2O
Lithium Oksigen gas Lithium Oxide
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Group 1 elements also react with bromine gas to form metal bromides.
Complete the chemical equation following.
2Li + Br2 2LiBr
Na + Br2 ..
K + Br2 ..
7. Reactivity of elements in Group 1 :
When going down Group 1,
the proton number are ..
the number of shells occupied with electrons are
the atomic size of atoms are
the single valence electron becomes away from the nucleus.
the force of attraction between the nucleus and valence electron (nuclei attraction)
becomes
it is for the atom to donate the single valence
electron to achieve the stable octet/duplet electron arrangement of the atom
of Noble gases.
Reactivity increases when going down the group!
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Alkali metals have one valence electron in their outermost occupied shells.Each of them reacts by donating one electron from its outermost occupiedshell to form an ion with a charge of +1, thus achieving the stable electron
arrangement of the atom of noble gas.
Example :
Na Na+ + e K K+ + e2.8.1 2.8 2.8.8.1 2.8.8
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Activity4 :-
1. Table below shows the electron arrangements of element W, X and Y.Arrange the elements in ascendingorder of reactivity.
Element Proton Number ElectronArrangement
W 11 2.8.1
X 3 2.1
Y 19 2.8.8.1
Answer: .
[ Size of atom increases when the number of shells filled with electrons increases]Safety precautions in handling Group 1 elements
Alkali metals are very reactive. Safety precautions must be taken when handling alkalimetals.
The elements must be stored in paraffin oil in bottles Do not hold alkali metals with your bare hands Use forceps to take them Wear safety goggles
Wear safety gloves Use a small piece of alkali metal when conducting experiments
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X
a
W
b
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E GROUP 17 ELEMENTS
1. Write the symbol of elements in Group 17.
Fluorine Chlorine Bromine Iodine Astatine
2. Group 17 elements are known as ..
3. Halogens exist as diatomic molecules.{ F2, Cl2, Br2, I2 }
4. Halogens have .. valence electrons.
5. All Group 17 elements are non-metals.
6. Write the symbol in the boxes for all the element in Group 17 in thePeriodic Table of Elements :
17
7. Write the proton number and electron arrangement :
Elements Proton number Electron
arrangement
F
Cl
Br 35 2.8.18.7
I 53 2.8.18.18.7
At 85 2.8.18.32.18.7
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F Cl Br I At
Proton number : ....
Number of protons :
Number of electrons :
Number of shells occupied with
electrons : ...
Atomic size :
Molecular size : ..
Going down the group :
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8. Physical properties of elements in Group 17 :
(i) Complete the table below :
ElementSymbo
lProtonNumber
ElectronArrangemen
t
Meltingpoint /
oC
Boiling
point /oC
Physicalstate atroomTemp.
Colour
Flourine 9 -220 -188
Chlorine 17 -101 -34
Bromine 35 2.8.18.7 -7 59
Iodine 53 2.8.18.18.7 114 184
(ii) Physical state of halogens at room temperature, 25 oC :
Fluorine and chlorine are ............... , bromine is a ..................... and iodine isa ...............
(iii) The colour of the elements becomes .. going down the group.
(iv) Halogen have melting and boiling points because their molecules
are attracted to each other by . inter-molecular forces. (Van der Waals
force : force of attraction between molecules).
(v) When going down the group, the melting and boiling points increases /decreases.This is because :
the molecular size ..
Forces of attraction between molecules becomes
Need . energy to overcome the forces of attraction betweenmolecules.
the melting and boiling points ..
9. Chemical Properties
(a) React with waterto produce two acids.
Example :
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Chlorine
gas
water
In general :
Br2 + H2O HBr + HOBr
Halogen : F, Cl, Br, I
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Cl2 + H2O +
Chlorine gas Hydrochloric acidHypochlorus acid
Br2 + H2O +
I2 + H2O +
(b) React with hot iron/ferum to produce iron(III) halides.
Example :
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HX and HOX solutions are ...
HOX solution exhibits property.
Hydrobromic acid Hypobromus acid
Hydroiodic acid Hypoiodus acid
Potassium
manganate(VII)
Iron wool
Heat
Concentratedhydrochloric acid
Combustion tube
Soda lime
To absorb excess
Cl2
gas that is
poisonous so that
it does not escape
to the enviroment.
To produce Cl2
gas
Bromine
water
water
Heat
Iodine
(solid)
water
Heat
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2Fe + 3Cl2 2FeCl3
Iron(III) chloride
Fe + Br2
Iron(III) .....................
Fe + I2
Iron(III) .....................
(c) Halogen reacts with sodium hydroxide, NaOH solution to produce
, .. and water.
Example :
2KOH + Cl2 KCl + KOCl + H2O
Potassium Sodiumchloride chlorate(I)
KOH + Br2 + + H2O
Potassium Potassiumbromide bromate(I)
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Chlorine
gas
Sodium hydroxide
solution
Solid
iodine
Heat
Iron
wool
Heat
Alkali
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LiOH + I2 + + H2O
Chemical properties of all elements are . because the number ofvalence electrons are the same and attain/achive the Noble gas arrangement in asimilar way.
10. Reactivity of Group 17 elements :
When going down Group 17,
the proton number are
the number of shells occupied with electrons are
the atomic size of atoms are
the outermost occupied shell of each halogen atoms becomes
away from the nucleus.
the nuclei attraction forces to attract one electron into the outermost occupied
shell by the nucleus becomes
it is for the atom to attract one electron to achieve stableoctet/duplet electron arrangement of the atom of Noble gas.
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Halogens have seven valence electrons in their outermost occupied shells.Each of them reacts by receiving one electron in its outermost occupied shell to forman ion with a charge of -1, orby sharinga pairofelectrons thus achieving the stableelectron arrangement of the atom of noble gas.
Example :
F + e F- Cl + e Cl-
2.7 2.8 2.8.7 2.8.8
Complete the electron arrangement for the atoms and molecule of flourine below :
two fluorine atoms Fluorinemolecule ( F
2)
Exists as diatomicmolecules [ 2 atoms of elements sharinga pairof its valenceelectron ] to achive the stable octet electron arrangement.
F F F F
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The strength of halogen atom to attract electron decrease from Fluorine to
Astatine [Electronegativity decreases]
this causes the reactivity down the group.
Activity 5 :-
1
Chlorine, bromine and iodine have . number ofvalence electrons.
When halogens take part in chemical reactions, their atom always gain
. electron to achieve . electron arrangement / a
stable electron arrangement.
2
The explanation
The atomic size . down the group.
The distance of the outermost shell becomes from the nucleus.
The force of attraction of the nucleus on the electrons of the outermost shell
..
The tendency of an atom to receive .. electron to achieve an octet
electron arrangement .
3
The explanation
The atomicsize of flourine is . than chlorine.
The between nucleus of fluorine atom and valence
electrons are .
Fluorine atom can electron easily.
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Chlorine, bromine and iodine have similar chemical properties.
Do you know WHY???
The reactivity of halogens decrease down the group.
Do you know WHY???
Why fluorine atom forms a negative ion more easily
than chlorine?
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Safety precautions in handling Group 17 elements
1. The vapour of flourine, chlorine and bromine are
2. The following precaution should be taken when handling halogen :
a) Halogen gas and liquid should be handled inside a
b) Wear safety when handling halogen fumes.
c) Wear safety when handling halogen materials.
Activity 6 :-
1. Elements X, Y and Z are in the same group in the Periodic Table of Elements.
Element X Y Z
Proton number 9 17 35
(a) What is the valence electron of the elements X, Y and Z?
(b) Which group in the periodic table can you find the elements X, Y and Z?
(c) Element Y can react with water.State two chemical properties of the solution produced?
(d) Write an equation for the reaction between element Z and hot iron.
2. (a) List all halogen elements from the top to the bottom of Group 17.
.
(b) Which are the most reactive and least reactive halogen?
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Most reactive : , least reactive : .............
3. Write the chemical equations for the following reaction :
(a) Chlorine with water : ...
(b) bromine with iron : ...
(c) iodine with sodium hydroxide : ...
4. Explain the changes to the reactivityof halogens when going down Group 17.
The atomic size of halogen .. down the group.
The distance of the outermost shell becomes from the
nucleus.
Therefore, the force of attraction by the nucleus on the electrons in the
outermost shell becomes
The tendency of an atom to . one electron to achieve an
octet electron arrangement decrease.
This causes the reactivity down the group.
5. Explain the changes to the electronegativityof halogens when going down Group17.
The atomic size of halogen .. down the group.
The distance of the outermost shell becomes from thenucleus.
Therefore, the force of attraction by the nucleus on the electrons in the
outermost shell becomes
The tendency of an atom to . one electron to achieve an
octet electron arrangement decrease.
This causes the electronegativity down the group.
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F ELEMENTS IN A PERIOD
Properties of elements in Period 3
Complete the table below.
Element of Period 3 Na Mg Al Si P S Cl Ar
Proton number 11 12 13 14 15 16 17 18
Electronarrangement
2.8.1 2.8.8
Valence electron[ Group ]
1[ 1 ] [ ] [ ] [ ] [ ] [ ] [ ]
[ ]
Atomic size
Physical state atroom temperature
solid
Electronegativity
Electropositivity
The trends of changes acrossPeriod 3 (from leftto right)
1. The proton numberincreases by unit from one element tothe next element.
2. All the atoms of the elements have shells occupied/filledwith electrons.
3. The number ofvalence electrons in each atom increases from to..
4. The atomic radius/size of atom of the elements ..
This is due to increasing of nuclei attraction force on the electrons.
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5. The electronegativity of elements
This is also due to the ..of the nuclei attraction force on the
in the outermost shell and the in atomic size.
6. All the elements in Period 3 exist as .. except chlorine andargon which are
ACID-BASE properties of oxides ofelements in Period 3.
Na2O MgO Al2O3 SiO2 P4O10 SO2 Cl2O7
(oxides) .. oxide (. oxides)
Basic oxides reacts with acids to form . and ..
Example :
Na2O + 2HNO3 2NaNO3 + H2O
Acidic oxides reacts with alkalis to form . and ..
Example :
SO2 + 2NaOH Na2SO3 + H2O
Amphotericoxides can react with both acids and alkalis.
Na & Mg are ., Al is ., Si, P, S & Cl are .
The elements change from metals to metalloid and finally to non-metals across theperiod.
Uses of semi-metals (metalloids) in Industry
Semi-metals or metalloids are weakconductors of electricity. Semi-metals such assilicon and germanium are used as semiconductors.
Semiconductors are used to make diodes and transistors that widely used in themaking of microchips for the manufacture of electrical and microelectronicequipments such as computers, mobile phones, televisions, digital cameras andvideo recorders.
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SEMI-METALSe.g: silicon and germanium
used to make
. and .
widely used in the making of ..
for the manufacture of :
Activity 7 :-
1 Table below shows the symbol of element, proton number and atomic radius ofelements in Period 3.
Element Na Mg Al Si P S Cl Ar
Proton number 11 12 13 14 15 16 17 18
Atomic radius 0.156 0.136 0.125 0.117 0.111 0.104 0.099 -
Electronarrangement
(a)Complete the electron arrangement in the above table.
(b)When crossing the period from left to right, the atomic size decreases. Explain why.
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..and ..
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(c) Write the symbol of elements for metal, metalloid and non-metal.
Metal Metalloid Non-metal
1. .2. .
3. .
1. 1..
2. 3. 4.
(d) Table below shows the symbol of oxide compound when the elements in period 3 arereacted with oxygen.
Na2O MgO Al2O3 P4O10 SO2
Classify the oxides into basic oxide, acidic oxide and amphoteric oxide.
Basic oxide Acidic oxide Amphotericoxide
G TRANSITION ELEMENTS
1. Elements from Group . to Group . in the Periodic Table.
[ Between Group . to Group .]
2. All transition elements are ., thus, these elements have thefollowing properties :
solids with surfaces.
ductile
malleable
high tensile strength
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. melting and boiling points
.. densities
good .. of heat andelectricit
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3. Special Characteristics / Superior Properties ofTransition Elements
(i) ..(ii) (iii) .
Different Oxidation Numbers
Transition elements can form ions with different oxidation numbers when formingcompounds.
TransitionElement
OxidationNumber
Name of ion Ionicsymbol
Example of compoundFormula Name
Iron, Fe+2 Iron(II) ion Fe2+ FeCl2 Iron(II) chloride
+3 Fe3+ Iron(III) chloride
Copper, Cu+1 Copper(I) ion Cu2O
+2 Cu2+ Copper(II) oxide
Nickel, Ni+2 Ni(NO3)2
+3 Ni3+ Ni(NO3)3
Coloured Ions orCompounds
The colours of some aqueous solutions of ions of transition elements :
Name of Ionof transition element
Formula of Ionof transition element
Colourin aqueous solution
Chromate ion
Dichromate ion
Manganate(VII) ion
Iron(II) ion
Iron(III) ion
Copper(II) ion
Cobalt(II) ion
Manganese(II) ion
Chromium(III) ion
Nickel(II) ion
Examples of someprecious stones and the transition elements present which givetheir distinctive colours :
Precious Colour Transition Element
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Stone present
Ruby Red
Sapphire Blue
Emerald Green
Amethyst Purple
Act as Catalysts
Transition elements or its compounds can act as catalysts in certain reactions.Catalysts are chemicals which can increase the rate of a reaction.
Example :
Industrial Process ProductTransition element used
as catalyst
Haber Process
Contact Process
Ostwald Process
Activity 8 :-
1 Figure 1 below shows part of the Periodic Table of Elements.
H He
O
Mg Al
FIGURE 1
Based on Figure 1 above, answer the following questions :
(a) What is the element represented by the symbol Fe?
(b) In figure above, mark X in the boxes for all the transition element.
(c) State one specific characteristic of transition element.
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Fe
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(d) Write the electron arrangement for the Mg atom
(e) Write the chemical equation for the reaction between aluminium and oxygen
gas.
(f) Based on the above informations, which gas is more suitable to be used inmeteorological balloons?Give one reason.
2 Table 2 shows the proton numbers of element P, Q, R, S and T.
Element Proton number Electron arrangement
P 3
Q 6
R 9
S 11
T 17
TABLE 2
(a) Complete the electron arrangement for all elements above.
(b) In which Group is element S located in the Periodic Table of Elements?
......
(b) State two elements in Table 2 that shows the same chemicalproperties.Explain the answer.
...
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Helium Gas
light
notreactive
Hydrogen Gas
light
flammable colourless
.
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.
(c) (i) Between elements P and S, which one is more reactive?Explain your answer.
..
..
..
..
..
(d) Arrange the elements P, Q, R, S and T in order ofincreasing of atomic size.
END OF CHAPTER 4
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