INTRO
chemistry is the study of matter and the changes it undergoes
matter is anything that occupies space and has mass
classification of matter :
a) pure substance
a.1) element
a.2) compound
b) mixture
b.1) homogeneous mixture
b.2) heterogeneous mixture
STANDARD TEMPERATURE & PRESSURE
scientific purposes :
STP is specified as conditions at 32oF & 14.7 psia
fuel gases :
STP is specified as conditions at 60oF & 14.7 psia
CONCEPT OF MOLE
its symbol is mol
Avogadro's number = 6.022045 X 10 23
1 mol = 6.022045 X 10 23 particles
molar mass is the mass of substance that contains 1 mole
of the substance
molar volume is the volume occupied by 1 mole of any gases
1 mole of an ideal gas occupies 22.414 dm 3 @ 22.414 L at STP
RELATIVE ATOMIC MASS + RELATIVE MOLECULAR MASS
eg. O is 16 times heavier than 1/12 carbon-12,
thus its relative atomic mass is 16
eg. O2 is 32 times heavier than 1/12 carbon-12,
thus its relative molecular mass is 32
EMPIRICAL FORMULA + MOLECULAR FORMULA
eg. glucose
its empirical formula is CH2O
its molecular formula is C6H12O6
PERIODIC TABLE
each column is called a group
each row is called a period
atomic number is the number of proton(s) or electron(s)
in a NEUTRAL atom
some selection :
| name |
symbol |
atomic number |
electron arrangement |
| carbon |
C |
6 |
2.4 |
| oxygen |
O |
8 |
2.6 |
| sodium |
Na |
11 |
2.8.1 |
| magnesium |
Mg |
12 |
2.8.2 |
| aluminium |
Al |
13 |
2.8.3 |
| chlorine |
Cl |
17 |
2.8.7 |
| potassium |
K |
19 |
2.8.8.1 |
| iron |
Fe |
26 |
2.8.14.2 |
| cobalt |
Co |
27 |
2.8.15.2 |
| copper |
Cu |
29 |
2.8.18.1 |
| tin |
Sn |
50 |
2.8.18.18.4 |
| mercury |
Hg |
80 |
2.8.18.32.18.2 |
| lead |
Pb |
82 |
2.8.18.32.18.4 |
ANCIENT NAME
antimony = stibium (Sb)
copper = cuprum (Cu)
gold = aurum (Au)
iron = ferrum (Fe)
lead = plumbum (Pb)
mercury = hydrargyrum (Hg)
potassium = kalium (K)
silver = argentum (Ag)
soldium = natrium (Na)
tin = stannum (Sn)
tungsten = wolfram (W)
MONATOMIC IONS
some common examples :
| name1 |
symbol |
name2 |
| iron (III) |
Fe3+ |
ferric |
| iron (II) |
Fe2+ |
ferrous |
| copper (II) |
Cu2+ |
cupric |
| copper (I) |
Cu+ |
cuprous |
| cobalt (III) |
Co3+ |
cobaltic |
| cobalt (II) |
Co2+ |
cobaltous |
| tin (IV) |
Sn4+ |
stannic |
| tin (II) |
Sn2+ |
stannous |
| lead (IV) |
Pb4+ |
plumbic |
| lead (II) |
Pb2+ |
plumbous |
| mercury (II) |
Hg2+ |
mercuric |
| mercury (I) |
Hg22+* |
mercurous |
*mercury (I) ions always occur bound together to form Hg2
IONIC BONDING + COVALENT BONDING
ionic bonding is formed by transfer of electron(s) from metal atom(s)
to non-metal atom(s)
eg. NaCl
covalent bonding is formed by sharing of electron(s) between
non-metal atoms
eg. CH4 , CO2 , O2
SIMPLE CHEMICAL EQUATION
eg. CH4 + O2 ---> CO2+ H2O
CH4 : C(-4x1) H(+1X4)
O2 : covalent bonding
CO2 : C(+4x1) O(-2X2)
H2O : H(+1x2) O(-2X1)
STOICHIOMETRY
it is the quantitative study of products and reactants in chemical reactions
eg. methanol (CH3OH) burns in air according to the equation
2CH3OH + 3O2 ---> 2CO2 + 4H20
if 209 g of methanol are used up in the combustion, what is the mass of water
produced ?
molecular mass of CH3OH = 12 + (1x3) + 16 + 1 = 32 g
mole of CH3OH = 209 / 32 ≈ 6.53 mol
by ratio, mole of H20 ≈ 6.53 X 2 ≈ 13.06 mol
molecular mass of H20 = (1X2) + 16 = 18 g
mass of H20 being produced ≈ 13.06 X 18 ≈ 235 g
ELECTROLYSIS
cathode = the negative electrode
anode = the positive electrode
cation = the positive ions that move towards the cathode
anion = the negative ions that move towards the anode
eg. in a molten NaCl, there are Na+ and Cl-
at cathode ( reduction - receiving electron ) :
2Na+ + 2e- ---> 2Na(l)
at anode ( oxidation - releasing electron ) :
2Cl- ---> Cl2(g) + 2e-
the overall process is :
2Na+ + 2Cl- ---> 2Na(l) + Cl2(g)
REDOX
the term redox comes from reduction and oxidation
redox reaction is a reaction involving reduction and oxidation simultaneously
reduction & oxidation can be defined as :
1) gain / loss of oxygen & hydrogen
2) gain / loss of electron
3) increase / decrease in oxidation number
eg 1 :
H2O(g) + Mg(s) --->
MgO(s) + H2(g)
H2O being reduced to H2
LOSS OF OXYGEN
Mg being oxidized to MgO
GAIN OF OXYGEN
eg 2 :
Pb(s) + O2(g) ---> 2PbO(p)
O2 being reduced to 2O2-
GAIN OF ELECTRON
Pb being oxidized to Pb2+
LOSS OF ELECTRON
eg 3 :
2FeCl3(aq) + SnCl2(aq) --->
2FeCl2(aq) + SnCl4(aq)
Fe3+ being reduced to Fe2+
DECREASE IN OXIDATION NUMBER
Sn2+ being oxidized to Sn4+
INCREASE IN OXIDATION NUMBER
REACTIVITY SERIES
K
Na
Ca
Mg
Al
C
Zn
H2
Fe
Sn
Pb
Cu
Hg
Ag
Au
-----<-----more reactive-----<-----
ELECTROCHEMICAL SERIES
K
Na
Ca
Mg
Al
Zn
Fe
Sn
Pb
H2
Cu
Hg
Ag
Au
----<-----more electropositive-----<----
more electropositive = higher tendency to release electron and become cation
REDOX SERIES
K
Na
Ca
Mg
Al
Zn
Fe
Sn
Pb
H2
Cu
Hg
Ag
Au
+1
+1
+2
+2
+3
+2
+2
+2
+2
+1
+2
+2
+1
+2
----<---stronger reducing agent---<----
---->---stronger oxidising agent--->----
ACID & BASE
acid-base reaction @ neutralization reaction :
acid + base ---> salt + water
acid = donor of hydrogen ions , H+
there are 2 types of acid : mineral acid & organic acid
eg. of mineral acid :
hydrocloric acid
HCl
sulphuric acid
H2SO4
nitric acid
HNO3
eg. of organic acid :
ascorbic acid
C6H8O6
citric acid
C6H8O7
malic acid
C4H6O5
tartaric acid
C4H6O6
base = donor of hydroxide ions , OH-
alkali = base that is soluble in water ; most base are alkali
eg. of base :
copper (II) oxide
CuO
iron (III) oxide
Fe2O3
lead (II) hydroxide
Pb(OH)2
eg. of alkali :
sodium hydroxide
NaOH
potassium hydroxide
KOH
aqueous solution of ammonia
NH3 (aq)
the units of concentration : g dm-3 @ mol dm-3
strong acid has high degree of dissociation in water to produce
H+
strong alkali has high degree of dissociation in water to produce
OH-
eg. of strong acid are HCL , H2SO4 , HNO3
eg. of strong alkali are NaOH , KOH
HYDROCARBONS
classification of hydrocarbons :
a) aliphatic (without benzene ring)
b) aromatic (with one or more benzene rings)
b.1) alkanes , CnH2n+2 where n = 1, 2, ..........
b.2) alkenes , CnH2n where n = 2, 3, ..........
b.3) alkynes , CnH2n-2 where n = 2, 3, ..........
the first 10 alkanes :
methane CH4
ethane C2H6
propane C3H8
butane C4H10
pentane C5H12
hexane C6H14
heptane C7H16
octane C8H18
nonane C9H20
decane C10H22
MACHINERY SIZING
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STEAM
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ATMOSPHERIC AIR
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IDEAL GAS + REAL GAS
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COMPRESSIBLE FLUID IN CLOSED CHANNEL FLOW
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INSTRUMENTATION & CONTROL
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