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CHE 102 BASIC GENERAL CHEMISTRY II (4 UNITS)
Course synopsis
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Qualitative and quantitative analysis in organic chemistry;
stereochemistry
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Electronic theory in organic chemistry,
saturated hydrocarbons; alkanes, unsaturated hydrocarbons; alkenes, alkynes and aromatics
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Periodic Table and Periodic properties; periodic law, Morseley’s
Law, valence forces, structure of solids, molecular and ionic forces
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Quantitative analysis
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This is the chemistry of all the elements in the Periodic Table; their compounds and interaction with each others
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It involves the electronic structures, physical properties,
reactions under various conditions; pressure, temperature and in vacuo
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This is not as systematic as Organic chemistry; each
element/compound has its own unique characteristic
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Periodic Table is the systematic arrangement of elements in a chart according to their atomic numbers
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However, later discoveries and development made use of atomic number, Z, according to the observation of
Morseley using information obtained from the α-scattering experiments
...
Morseley noted that the frequency ν of x-ray
emitted from elements can be correlated by this equation
√ 𝑣 = a(Z – b)
Where v = frequency, a and b are constants that are same for all elements and Z = atomic number
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It was observed that all elements within the same vertical column share similar outermost electronic configuration
and subsequently same physical and chemical properties
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The horizontal row
known as the Period that displays elements with increasing atomic number Z and the progressive filling of their
outermost orbital shell
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The Main Group or Representative elements are the elements in Group IA, IIA, and IIB to VIIB
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Noble gases in Group 0, VIIIB

or 18 have completely filled p-orbital with exception of He that has completely filled s-orbital
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They readily form cations with incompletely filled d-sub shells or orbitals
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The elements in these two classes are characteristically radioactive
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For instance, all elements in Group IA – Alkali metals have similar outermost electronic configuration;
each has a noble gas core and ns1 outer electron
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These outer electrons are usually the ones involved in chemical
bondings and they are called the VALENCE ELECTRONS
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Periodic Law
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Progressing from the lightest to the heaviest atoms, certain properties of the elements approximate those of their
precursors at regular intervals of 2, 8, 18 and 32
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Similarly the chemical
family of halogens comprising of element 9 (F), 17 (Cl), 35 (Br), 53 (I) and 85 (At) show similar properties
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The electrons in the outermost configurations of elements are usually involved in bonding during chemical
reactions and these electrons are known as the valence electrons
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As
a rule, the elements most likely to form cations are the alkali and alkaline-earth elements and the elements most
likely to form anions are halogens and oxygen
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For instance, reaction between Li (1s22s1) and F (1s22s22p5) leads to each of the participating atoms to assume inert
gas configuration in forming ionic compound
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Since the reaction occurs as a result of ions, the valence force is
therefore electrovalent or electrostatic
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F

F

In such reactions, formation of molecules illustrates Octet Rule
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O : : C : : O or O=C=O
The valence force holding covalent molecules together is van der Waal force
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Property

NaCl

Appearance

White solid

Melting Point 0C

801

Molar heat of fusion (kJ/mol)
Boiling Point 0C
∆H vaporization (kJ/mol)

CCl4
Colourless liquid
-23

30
...
5
76
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17

1
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Intramolecular forces hold atoms together in a molecule
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Electrovalent compounds having ionic linkages are made up of positive and negative ions arranged together in a
regular way in a LATTICE
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Thus, considerable amount of energy is required to melt the solid and this has to break the
lattices
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Covalent compounds are made up of discrete molecules
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In solid, the only force between molecules is weak van der Waal forces
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Hence, most
covalent compounds are gases, liquids and soft solids with low melting points
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In these cases, there are strong forces operating in
all directions
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Structures of solids
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Crystalline solid possesses rigid and long-ranged
orders; its atoms, molecules or ions occupy specific positions
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The forces responsible for the
stability of crystal can be ionic, van der Waal forces, hydrogen bond or a combination of these forces
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Amorphous solids such as glass lack well-defined arrangement and long-ranged molecular orders
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The structure and properties of crystals such as melting and boiling points, density and hardness are determined
by the kind of forces that hold the particles together
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Ionic crystals
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There are types of ionic structures;
1
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3
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Example of isomeric crystal like iron pyrite

Isometric Crystal
Isometric crystals, such as the pyrite shown here, have three perpendicular axes of equal
length
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The pyrite
crystal system forms rocks that are fairly hard, but quite brittle
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Dorling Kindersley
Microsoft ® Encarta ® 2009
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All rights reserved
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Three of the
axes are of equal length, and are symmetrically placed in one plane
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Dorling Kindersley
Microsoft ® Encarta ® 2009
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All rights reserved
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Ionic Bonding: Salt
The bond (left) between the atoms in ordinary table salt (sodium chloride) is a typical ionic
bond
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This electron exchange is reflected in the size difference between the atoms before and
after bonding
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© 1993-2008 Microsoft Corporation
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Tetragonal Crystal
This Siberian idocrase has a tetragonal crystal structure
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Idocrase is grouped with rocks such as zircon, rutile, and wulfenite,
which are rocks of medium hardness that may possess a diamondlike fire
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© 1993-2008 Microsoft Corporation
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Covalent Crystals
In this the atoms are held in an extensive 3-dimensional network entirely by covalent bond
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These two have different crystal structures
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Allotropic Forms of Carbon
Atoms of the element carbon can link together in several ways to form substances with very
different properties
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Graphite is made up of layers of carbon that can slide over each other easily, making
graphite a useful lubricant
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© Microsoft Corporation
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Microsoft ® Encarta ® 2009
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All rights reserved
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Property

Diamond

Hardness

Very hard, in fact the hardest

Graphite
Soft and slippery

Known substance
Hybridization

sp3 with no ∏ electrons

sp2 hybridized like benzene with ∏ electrons
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Density (g/cm3)

3
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22

pressure of 50 – 60,000 atmospheres
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Forces

Strong covalent force

van der waal force

Molecular crystals
Typical examples of molecular crystals are solid SO 2, I2, P4 S8 and ice
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The attractive forces are van der waal and or hydrogen bonding
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Most melt at temperature below 100 0C
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In metals, the lattice points are occupied by atoms of the same metal
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Metallic elements are very dense
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In fact, atoms in a metal have an array of positive ions immersed in a sea of
delocalized valence electrons
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Mobility of the delocalized electrons makes metals good conductor of electricity and heat
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The negatively charged electrons distribute themselves
throughout the entire piece of metal and form nondirectional bonds between the positive
silver ions
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A force applied to a malleable
substance shifts the positions of the atoms without breaking the bonds that hold them
together
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All Rights Reserved
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© 1993-2008 Microsoft Corporation
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General properties of crystals
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Sucrose, C12H22 O11

Metallic bonds
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g
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Reactivity Series
Chemists can list metals according to how quickly they undergo chemical reactions, such as
burning or dissolving in acids
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A metal at the top of
the series generally reacts more vigorously than those that are below it in the series, and
the more reactive metal can take their place (or displace them) in various compounds or in

solution
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© Microsoft Corporation
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Microsoft ® Encarta ® 2009
...
All rights reserved
...

To fully appreciate Inorganic Chemistry, some elements or groups of elements are selected to illustrate the
behaviours of these substances
...
The metals of
interest are Alkali and Alkaline-earth metals, while halogens, hydrogen and oxygen are the non-metals slated for
discussions
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These are Group IA or 1 elements reputed to be the most reactive and electropositive elements
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They have one electron each in their
respective outermost electronic shell or sub-shell
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Element Configuration

Atomic radius Ǻ ionic radius Ǻ M P 0C S
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23

0
...
57

0
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97

496

K

[Ar] 4s1

2
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33

63

0
...
16

1
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53

403

Cs

[Xe]6s1

2
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67

29

1
...
54

520

From this table, it is obvious that the behaviours of the elements follow some trends
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On the other
hand, the melting point and the first ionization energy decrease down the group from Li to Cs
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Sodium and its compounds are of great importance
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There are other important
industrial uses
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S
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Potassium salts, usually sulphate are used in fertilizer
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Both Na+ and K+ are of physiological importance in animals and
plants; cells can differentiate between Na+ and K+ ions probably in some types of complexing mechanisms
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Preparation and properties of metals
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Due to low melting point and ready vaporization of K, Rb and Cs; they are rather made by treating their molten
chlorides with Na vapour
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These metals are
highly electropositive and they react readily with most other elements and many compounds on heating
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Li react slowly with water at 25 0C and will not replace the weakly acidic H in C6H5C=CH while other metals do
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Li can be used to absorb N2
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They tarnish rapidly in air to form M 2O oxides
with oxygen
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4Na + O2 → 2Na2O
4Li + O2 → 2Li2O
In air or O2 at 1 atmosphere of pressure, the metals burn
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K, Rb and Cs form
superoxide MO2
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2C2H5OH + 2 Na → 2C2H5 ONa + H2
The metals dissolve in ammonia to give a blue solution when dilute and copper colour solution when the ammonia
is concentrated
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They also react with
ammonia to form amide and hydrogen
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Compounds
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2Na + Cl2 → 2NaCl
Li + H → LiH
The chlorides and hydrides are highly electropositive and ionic
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Lithium shares some diagonal relationship with Mg in Group IIA making it uniquely different from other elements
in its group
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g
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These are formed by the dissolution of metals or their oxides in water
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2KOH + CO2 → K2CO3 + H2O
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KOH + HCl → KCl + H2O
2NaOH + H2SO4 → Na2SO4 +2H2O
CH3COOH + NaOH → CH3COONa + H2O
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These metals react readily with halogens to form ionic halides
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These halides dissociate in water to form cations M + and halide anions
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The carbonates and bicarbonates are formed by reactions between metal oxides, hydroxides and CO2
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Both carbonates
and bicarbonates react with acids to form salts, water and liberate CO2
...


K2O + CO2 → K2CO3
K2CO3 + H2O + CO2 → 2KHCO3
2NaOH + CO2 → Na2CO3 + H2O
Na2CO3 + 2HCl → 2NaCl + H2O + CO2
KHCO3 + HCl → KCl + H2O + CO2
2NaHCO3 → Na2CO3 + CO2 + H2O

Sulphate
Their metals, oxides, hydroxides, carbonate and bicarbonate form sulphates with sulphuric acid
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2Na + H2SO4 → Na2SO4 + H2
Na2O + H2SO4 → Na2SO4 + H2O
2KOH + H2SO4 → K2SO4 + H2O
2CsCO3 + H2SO4 → Cs2SO4 + H2O + CO2
2KHCO3 + H2SO4→ K2SO4 + 2CO2 + 2H2O

Nitrates
The metals, oxides, hydroxides, carbonates and bicarbonates react with nitric acid to form nitrates
...

2HNO3 + K2O → 2KNO3 + H2O
Na2CO3 + 2HNO3 → 2NaNO3 + H2O + CO2
LiOH + HNO3 → LiNO3 + H2O
However, the reaction of metals with this acid is very violent, hence not to be indulged in
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2NaNO3 → 2NaNO2 + O2
2KNO3 → 2KNO2 + O2
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The metals react directly with hydrogen to form ionic and electrovalent hydrides
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2K + H2 → 2KH
2Li + H2 → 2LiH
2Na + H2 →2NaH
2LiH + H2O →LiOH + H2

GROUP 2 OR IIA OR ALKALINE-EARTH METALS
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They all have
two valence s-electrons in their outermost orbitals
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They form colorless ionic compounds
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Element Configuration Atomic radius Ǻ Ionic radius Ǻ Density M
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oC Ionization energy (KJ/Mol)
Be

[He] 2s2

Mg

[Ne] 3s2

Ca

0
...
31

1
...
36

0
...
7

650

1450

[Ar] 4s2

1
...
99

1
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91

1
...
6

768

1064

Ba

[Xe] 6s2

1
...
35

3
...
50

5
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Occurrence: Mg and Ca are abundant and are among the eight most abundant elements in nature/earth crust
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Mg occurs in seawater as
deposit of Magnesite MgCO3, dolomite MgCa(CO3)2, Kieserite MgCl3
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CaCO3 is found extensively as Calcite
and Limestone
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Radium only occurs in nuclear reactor with a half-life of seconds
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The metals being less reactive than those in Group IA, react with water, especially steam to form hydrogen and
hydroxides
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The bases absorb CO2 from air to form carbonates and
bicarbonates
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The metals burn in air to form basic oxides
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2Mg + O2 → 2MgO
MgCO3 → MgO + CO2
Ca(OH)2 → CaO + H2O
Ba(NO3)2 → BaO + 2NO2 + O2
CaSO4 → CaO + SO2 + O2
The stability of the carbonates to heat increases from Be to Ba e
...

Halides are formed from reactions between metals and halogens or between metal oxides, hydroxides and
halogen or hydrogen halides
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MgCO3 + 2HNO3 → Mg(NO3)2 + CO2 + H2O
CaO + 2HNO3 → Ca(NO3)2 + H2O
Sr(OH)2 + 2HNO3 → Sr(NO3)2 + 2H2O
Ca + 3HNO3 → Ca(NO3)2 + NO2 + H2O
The nitrates are thermo-labile decomposing to oxides, nitrogen oxides and oxygen on heating
...

Ca + H2SO4 → CaSO4 + H2
Mg(OH)2 + H2SO4 → MgSO4 + 2H2O
BaO + H2SO4 → BaSO4 + H2O
SrCO3 + H2SO4 → SrSO4 + CO2 + H2O
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The
sulphates are equally thermo-labile with stability to heat increasing down the group from Be to Ba
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MgSO4 → MgO + SO3
CaSO4 → CaO + SO3
They all form ionic hydride by direct reaction of metals with hydrogen
Mg + H2 →MgH2
Sr + H2 → SrH2
Ca + H2 → CaH2
Be + H2 → BeH2
Ba + H2 → BaH2
They also form ionic carbides by direct reaction of metal oxides with carbon at high temperature
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CaO + 3C → CaC2 + CO
Ca + 2C → CaC2
CaC2 + 2H2O → C2H2 + Ca(OH)2
Calcium carbide react atmospheric nitrogen to form calcium cyanide
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This is the first member of the Periodic Table with atomic number 1, and has only one proton devoid of neutron in
its nucleus
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Atomic hydrogen only exists at high temperature
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H(g) + H(g) → H2(g)
Molecular hydrogen H2 is colorless, odourless and non-toxic gas
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9 0C
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It is also the tenth most abundant element in the earth crust where it
is found in combination with other elements
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On the ground state, hydrogen has a configuration of 1H
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On the other hand, hydrogen resembles the halogens in its uni-negative hydride ion H-;
which is isoelectronic with He (1s2)
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Hydrogen occurs in 3
isotopic forms; 1H, 21D and 31T
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Preparation
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Zn + 2HCl → ZnCl2 + H2
H2SO4 + Mg → MgSO4 + H2
Electrolysis of water, dilute HCl, NaOH and NaCl is also another way of producing hydrogen
...
Commercially, hydrogen can be obtained from reaction between propane and water
at 900 0C in presence of a catalyst
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C3H8 + 3H2O → 3CO + 7H2
C(s) + H2O(g) → CO(g) + H2(g)
Properties
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Hydrogen reduces oxides of metals lower than it in the electrochemical series
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2
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CH2=CH2 + H2 → CH3CH3
Hydrides
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1
...

3
...
These hydrides
are solid with high melting point temperatures
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2Li + H2 →2LiH
Mg + H2 → MgH2
H-(aq) + H2O → OH- + H2
LiH + H2O → LiOH +H2
Covalent hydrides are formed with elements in Groups IIIA to VIIA
...

Interstitial hydrides are the non-stochiometric hydrides usually formed with transitional metals like iron,
vanadium, nickel e
...
c
...
g
...
8, TiH2
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Halogens are reactive non-metals belonging to Group VIIA; and these include fluorine, chlorine, bromine, iodine,
astatine and lately, unuseptium
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Property

F

Cl

Br

I

2s22p5

3s23p5

4s24p5

5s25p5

Melting point oC

-223

-102

-7

114

Boiling point oC

-187

-35

59

183

Valence electron
Configuration

Atomic radius (Ǻ)

0
...
99

1
...
33

Ionic radius (Ǻ)

1
...
81

1
...
16

Ionization energy

1680

1251

1139

1003

4
...
0

(kJmol-1)
Electronegativity

Electrode potential (V) 2
...
6

2
...
5

1
...
07

0
...
7

192
...
0

X-1(kJmol-1)
Element Astatine (At) is unstable
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Preparation
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Electrolysis of fluorides and chlorides
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At cathode: 2H+ + 2e → H2(g)
Overall 2HF(l) → H2(g) + F2(g)
Electrolysis of brine 2NaCl + 2H2O through electrolysis → 2NaOH(l) + H2(g) + Cl2(g)
...


Compounds of halogens
...


Hydrogen halides can be prepared by direct combination of the elements
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HCl and HF can also be prepared from reaction
between metal halides and concentrated H2SO4
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This can be achieved by reacting bromine with phosphorus and
then dissolve in water
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Metallic halides
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2Na + Cl2 → 2NaCl
2Fe + 3Cl2 → 3FeCl3
Mg + F2 → MgF2
The metal halides are ionic salts
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2Na + 2HF → 2NaF

K2O + 2HCl → 2KCl + H2O
Ca(OH)2 + 2HCl → CaCl2 + 2H2O

Uses of halogens
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It is used as a bleaching agent In the textile and paper industries
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Fluorine is useful in the production of refrigerant Freon and Teflon (Polytetrafluoroethylene) It is also used in the
separation of 235U and 238U isotope in form of UF6
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Iodine is a constituent of thyroid hormone, thyroxin
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A salt of iodine with silver AgI is used in seeding clouds for artificial rainfall
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Element

Electronic configuration

Nitrogen

[He]2s22p3

Phosphorus

[Ar]3s23p3

Oxidation State
-3, -2, -1,0, 1, +3, +5
+3, +5

Abundance
19mg/kg
1120mg/kg

M
...
0C

B
...
0C

-210

-196

44

281

Nitrogen and phosphorus are very important elements to life and agriculture in that they are major element of
fertilizers, nitrogen is a major component of the body building block; protein and nitrogen is responsible for
nitrogen fixation in plants
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Phosphorus in form of calium salt is a major component of bones
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Nitrogen occurs freely in the atmosphere where it is a major component of air in which it
constitutes 78% by volume of air
...
Phosphorus occurs mainly in form of Phosphate mineral like
phosphate rock Ca3(PO4)2

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