1. Fuels are substances, which burn to produce heat energy.
They can be solid, liquid or gas and primary or natural fuel and
secondary or processed fuel.
2. Calorific value is amount of heat produced by burning a unit
mass of fuel completely. It is measure in KJ/g.
Calorific Value = Heat Produced/ Fuel used
3. Ignition temperature of a substance is the temperature at
which the substance catches fire.
4. Destructive distillation is the process in which complex carbon
compounds are strongly heated in closed vessel in absence of oxygen
to break into simple form of carbon.
5. Destructive distillation of wood produces :- Wood gas, Tar,
Charcoal, Methyl Alcohol and acetic acid.
6. Destructive distillation of coal produces coal gas, ammonical
liquor, coal tar and coke.
7. Gas prepared by anaerobic fermentation of animal waste and
plants waste in presence of water is Biogas, which is a mixture
of Methane Carbon dioxide, Hydrogen and Hydrogen suphide.
8. Fractional distillation is the process used for separating
a mixture of liquids having different boiling points. Crude petroleum
is passed through a fractionating column. Fractions with higher
boiling points are collected in the lowest part and those with
low boiling points are collected at the top of the column.
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Petroleum gas
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C1-C4
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40o
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Used to prepare carbon black and gasoline
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Gasoline
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C5-C10
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40o-170o
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Fuel for vehicle
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Kerosene Oil
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C10-C12
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170o-250o
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Household and aviation fuel
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Diesel Oil
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C13-C15
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2500-350o
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Fuel for heavy vehicle
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Fuel Oil
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C15-C10
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350o-400o
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Fuel for furnace
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Lubricating Oil
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C17-C20
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400o
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Lubricating Machine
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Paraffin Wax
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C20-C30
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400o
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Candles Vaseline
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Asphalt
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C30-C50
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Making Road surface
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9. Liquefied petroleum gas is mainly butane with some propane
and ethane. Ethyl mercaptan C2H2SH is added to detect a leakage.
10. Cracking is the process of breaking up a higher hydrocarbon
into smaller saturated and unsaturated hydrocarbon molecules by
heat or a catalyst.
C12H26 Heat C7H16 + C5H10
Dodecane Heptane Pentene
Carbon Dioxide causes Green house effect i.e. rise in earth's
atm temperature. Carbon mono Oxide on inhalation mixes with haemoglobin
to form carboxy haemoglobin, which reduces the oxygen carrying
capacity causing suffocation and even death.
11. Flame is the region where the fuel burns. It is hot because
the energy released in forming new bonds of products is very large
as compared to the energy used in breaking the bonds within the
fuel.
12. Rocket propellant are rocket fuels e.g Liquid hydrogen synthetic
rubber, kerosene oil, liquid ammonia.An oxidiser is added to the
propellant e.g. liquid oxygen, liquid fluorine and hydrogen peroxide.
24. Respiration is the process, which burns our food slowly within
our body at 37°C. It is a complete combustion and carbon dioxide
water and energy are the products. Whereas combustion is a fast
process outside our body at high temperature and is usually incomplete
with carbon mono oxide and unburned carbon particles.
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Metal
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Non-Metal
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Are elements which form positive ions by losing electrons
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Are elements, which form negative ions by gaining electrons.
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| Oxides of metal are basic |
Oxides of non-metal
are acidic or neutral. |
| They have 1-3 electrons in the
outermost shell of their atom |
They have 4-8 electrons
in the outermost shell of their atom. |
| Metals are malleable, ductile,
good conductor of heat and electricity, lustrous, hard, sonorous
and have high density and high melting and boiling points. |
Non-metals are brittle,
non-ductile, bad conductor of heat and electricity, non-lustrous,
soft, non-sonorous and have low density and low melting and
boiling points. |
| Metals are electro positive. |
Non-metals are electronegative. |
| Metals react with water to form
metal oxide and H2 gas |
Non-metals do not react
with water as they can not give electrons to reduce to hydrogen
ions of water to H2 gas. |
| Metals reacts with dilute acids
by displacing hydrogen |
Non-metals do not reacts
with dilute acids as they have no electrons to supply to hydrogen
ion. |
| Reaction of metals with chlorine
forms metal chloride (electrovalent compounds) |
Non-metals reacts with
chlorine to form covalent chloride. |
24. Arrangement of metals in order of decreasing reactivity is
called reactivity series. Metals above hydrogen can displace hydrogen
and below can not do so.
K Na Ca Mg Al Zn Fe Sn Pb (H) Cu Hg Ag Au
More reactive metal than hydrogen less reactive metal than hydrogen
11. More reactive metals displaces less reactive metal from its
salt solution:-
Cu SO4 + Zn (S)-> SnSO4 + Cu (S)
(Aq) (Aq)
11. More reactive metals displaces less reactive metals from
its oxide:-
CuO + Mg --> MgO + Cu
11. Metals are reducing agents because they can give electrons
for reduction and non-metals are oxidizing agents because they
can accept electrons.
11. Minerals are materials in which metals and their compounds
are found in the earth. Those minerals which can be used to isolate
the metals are called ores.
Oxide ore: (Bauxite) Al2O3. 2H2O
Carbonate ore: (Calamine) ZnCO3, (Limestone) : CaCO3
Sulphide ore: (Zincblend) ZnS, (Cinnabar) HgS, (Copperglance)
Cu2S
Halide ore : (Rocksalt) NaCl, (Flourospar) CaF2
11. Metallurgy includes the processes involved in extraction
of metals from their ore:-
() Concentration of ore:- Purification by removing earthly particles,
sand
(i) Hydraulic washing (ores of tin and lead)
(ii) Frothfloatation process (sulphide ore)
(iii) Magnetic separation (iron and manganese)
(iv) Chemical separation (Aluminium ore)
(a) Conversion of concentrated ore into metal oxide:-
(i) Calcination : Ore is heated strongly in absence of air
(Carbonate ore)
(ii) Roasting : Ore is strongly heated in presence of air
(Sulphide ore)
(b) Metal oxide is reduced to metal:-
(i) By heating alone: 2HgS + 3O2 --> 2HgO + 2SO2
2HgO + O2.
(ii) Chemical reduction using carbon and aluminum done for zinc,
iron, copper.
ZnO + C --> Zn + CO
Fe2O3 + 3CO --> 2Fe + 3CO2
3MnO2 + 4Al --> 3Mn + Al2O3 (Hermite process)
iii) Reduction by electrolysis : Done in case of Al, Na, K, Mg
and Ca.
Molten salt is electrolyzed and metals are produced at negative
electrodes.
Al3+ + 3e- -----Electrolytic reduction----> Al
From
molten Al2O3
c) Refining of impure metals:-
(i) Liquation method : Done for metals with low melting points
(Sn, Pb)
(ii) Distillastion method : Done for Mercury
(iii) Oxidation method : Done for iron (oxygen oxidises the
impurities leaving the metal)
(iv) Electrolytic refining : Done for copper and zinc.
12. Alloys are mixtures of one metal with one or more than one
metal (or non-metal)
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Duralium
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Al 95%, Mg 0.5%, Cu 04%, Mn 0.5%
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Kitchen-ware and bodies of ships
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Magnalium
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Al 95%, Mg 0.5%
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Making of light instruments
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Steel
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Fe 98%, C 1.5% - 2%
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Construction of buildings
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Stainless Steel
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Fe 82%, (Cr+Ni) 18%
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Utensils
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Brass
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Cu 80%, Zn 20%
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Nut bolts and ornaments
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Bronze
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Cu 90%, Sn 10%
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Status coins medals
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German Silver
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Cu 60%, Zn 20%, Ni 20%
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Electroplating
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Compound of metals: NaCl Sodium Chloride (Table salt)
Na2CO3.10H2O Sodium carbonate
(Washing
Soda)
NaHCO3 Sodium Bicarbonate (Baking Soda)
CaO Calcium Oxide (Lime)
Ca(OH)2 Calcium Hydro oxide (Slaked lime)
CaOCl2 Calcium Oxy chloride (bleaching
powder)
(CaSO4)2.H2O Calcium Sulphate
dihydrate
(plaster of Paris)
23. Silicon is placed in group IV of the periodic table and can
be obtained from silicon di oxide (SiO2). Solution of sodium silicate
(Na2SiO3) i.e. water glass is used to prepare a silica garden
as crystal of coloured salts grow in it.
24. Phosphorous is placed in group V of periodic table and can
be prepared from rock phosphate i.e. Ca3(PO4). Phosphorous exists
in two physical states(Allotropes) white phosphorous and red phosphorous.
25. Sulphur is placed in group VI of the periodic table and exists
in both free and combine state. It is extracted from underground
by Frasch process.
26. Carbon is placed in group IV of the periodic table. It had
the property of self combination to form long chains(Catenation).
Carbon exists in two physical form diamond and graphite. Diamond
is a very hard substance because carbon atoms are bonded to one
another by a network of covalent bonds. It is not a good conductor
of heat and electricity. In graphite the carbon atoms are joined
to three other carbon atoms to form a flat hexagonal frame. The
layer of carbon atoms are held by vender wall force. Due to this
sheet structure graphite is a soft substance and because of one
free carbon atom it is good conductor of heat and electricity.
27. The compounds made out of carbon and hydrogen are called
hydrocarbons. A hydrocarbon with a single bond is called a saturated
hydrocarbon and a compound with double and triple bond is called
an unsaturated hydrocarbon.
| Saturated hydrocarbon: |
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Alkanes Cn H2n+2 (n is the number of carbon
atom in one molecule) |
| Unsasturated hydrocarbon : |
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Alkenes CnH2n (compound has double bond)Alkynes
CnH2n-2 (compound has triple bond) |
28. Hydrocarbon are named according to the rules set by IUPAC>
(a) The longset chain of carbon atoms in the compound is the
parent chain. If it is an alkane the suffix is (ane) if it has
a double bond the suffix is (ene) if it has a triple bond the
suffix is (yne).
(b) The groups present as a side chain are considered as substitutes
(c) The carbon atoms are numbered in such a way that alkyl group
gets the lowest possible number and the position of the substitute
group is indicated by writing the number of the carbon atom to
which it is attached.
(d) The name of the compound is obtained by writing the position
and name of the alkyl group before the name of the parent hydrocarbon.
1 2 3
4 H H
CH-3-CH - CH2 - CH3
\ /
| C=C Ethene
CH3
/ \
2 - Methyl Butane H H
