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OPEN CHAIN AND CLOSED CHAIN HYDROCARBONS In aliphatic hydrocarbons, the carbon atoms are attached to another carbon to form chains.These chains may be either open or closed (rings) chains.The open chains on the basis of saturation of valence are classified as saturated and unsaturated hydrocarbons. (i) Saturated Hydrocarbons: The compounds in which all the valencies of carbon carbon atoms are fully satisfied by single bonds,are called saturated hydrocarbons.The examples of saturated hydrocarbons are alkanes. (ii) Unsaturated Hydrocarbons: The compounds in which all the valencies of carbon atoms are not fully utilized,are called unsaturated hydrocarbons.Alkanes and alkynes are the example of unsaturated open chain hydrocarbons. The hydrocarbons which contain closed chain of carbon atoms are called cyclic hydrocarbons and examples are cyclo alkanes and cyclo alkenes. Aromatic compounds are benzene and its homologs.These compounds are further divided into homonuclear and hetero-nuclear ar...

CHLORINE ELECTROLYSIS METHOD: Chlorine is manufactured by the electrolysis of aqueous solutions of sodium chloride.For this purpose two cells are used which are described below: (a) NELSON'S CELL: This cell consists of U-shaped perforated steel vessel which acts as cathode and carbon rod as anode.This U-tube is separated from anode by asbestos layer on the inner wall of the U-Tube as shown in figure The U-tube is filled by aqueous solution of sodium chloride.On passing the electric current,chlorine is obtained at anode reaction: (i) Ionization NaCl ---------> Na + Cl (ii) Reaction at anode 2Cl - 2e ----------> Cl2 (b) CASTNER-KELLNER'S CELL: This cell has a Cathode consisting of layer of mercury at the bottom of cell which flows from right to left.Saturated solution of sodium chloride also flows slowly through the cell in same direction as the mercury.The anode rods are of graphite which dip into the solution of sodium chloride. On electrolysis chlorine is liberated at ...

ATOMIC HYDROGEN Ordinary hydrogen exists as diatomic molecules (H2). Therefore it is also called as molecular hydrogen.The two atoms in a molecule of hydrogen are held together by shared pair of electron known as covalent bond having very high bond energy (104 cal. mol-1.The molecules are very stable and dissociate into atoms only under extreme conditions.The product obtained as a result of dissociation of molecular hydrogen is known as atomic hydrogen. These atoms have very short life and quickly combine together to form molecules again. PREPARATION OF ATOMIC HYDROGEN:- Atomic hydrogen is prepared by thermal decomposition of ordinary hydrogen or by electrical dissociation under reduced pressure. H2 + 104K.cal -------------> 2H H2 ------------------------------>2H PROPERTIES OF ATOMIC HYDROGEN:- Atomic hydrogen is much more reactive than molecular hydrogen.Expected reactions of molecular hydrogen are only those in which more than 104K.cal per mole are evolved per two g...

REFINING OF PETROLEUM Petroleum is refined by distillation.Crude oil is carried by pipes to a fractionating column and heated to above 400 C.A number of products are obtained at different temperatures and condensed. More than 500 compounds have been formed in petroleum distillate boiling below 200 C.Gasoline or petrol is a mixture of hecane (C6H14) and heptane (C7H16) and Heptane (C7H16) Since the demand of gasoline is increasing due to to its increased use a fuel for automobiles, airplanes etc.The cracking is employed to obtain increased quantities of petrol from crude oil. REFORMING OF PETROLEUM :- Knocking is a sharp metallic sound produced in the internal combustion engine.Its a cause is gasoline of low octane number.T he octane number of gasoline is improved by reforming,a process some what similar to cracking,which again brings about the arrangements of straight chain alkanes into branched chain alkanes.If the petrol used is of such quality that its vapour mixed with air can...

NATURAL SOURCES OF ORGANIC COMPOUND The mineral sources of organic compound are coal,natural gas and petroleum.Plants are also among natural sources of important organic compounds. COAL :- The bituminous or soft coal is a very important source of organic compounds.This when subjected to destructive distillation, products of industrial importance are obtained. FRACTIONAL DISTILLATION OF COAL-TAR:- When coal is destructively distilled four principal fractions are obtained, viz: coal gas , coal tar ,coke and ammonical liquors. Of these coal gas which consists mainly of methane and hydrogen is used as a fuel,while coke a form of carbon,is used in the manufacture of iron and steel industry.The composition of coal tar varies depending on the nature of the coal.However, coal is composed of various aromatic hydrocarbons. These components are separated by fractional distillation of coal tar.It has been calculated that 100 Kg of coal tar yield 1-2 Kg of benzene. NATURAL GAS :- Natural...

LEAD PIGMENT Lead forms various types of pigments which are used to give the proper color to paints etc.Some of them are described below: White Lead pigment Red Lead Pigment Chrome Yellow Pigment Chrome Red Pigment Turner's Yellow Pigment (i) White Lead Pigment : It is a basic lead carbonate and has approximately composition as [ 2PbCO3.Pb(OH)2] or [Pb3.(CO3)2] Preparation : Chamber Process or Duch Process : When a mixture of the vapours of acetic acid and steam is passed into the chambers containing lead sheets (buckets) about 2-3 days,until the corrosion of lead is complete.By passing the mixture of CO2 and vapours of acetic acid through this corroded lead for about 3-4 weeks,the White Lead is formed on the surface of lead sheets.This product is then scratched,dried and packed. 2Pb +2CH3COOH + 2H20 ---------> [Pb(OH)2.Pb(CH3COO)2] + 2H2 3[Pb(OH).Pb(CH3COO)2] + 2H2O + 2CO2 -------------> 2[2PbCO3.Pb(OH)2] + 6CH3COOH A better "White Lead" is obtained by passing CO2 ...

TYPES OF ELEMENTS BASED ON ELECTRONIC CONFIGURATION The periodic table has been divided into s,p,d and f blocks on the basis of electronic configuration : (1) The Noble Gases : In the periodic table, the noble gases are found at the end of each period in zero group.They are colorless gases up to some extent chemically non reactive and diamagnetic. The electronic arrangement of ns2,np6 is exceptionally stable.Discontinuities in energy level diagram occur after these configurations are attained.With the exception of helium (Z=2) all the noble gases have outer electronic configuration of 2s2,2p6 no atom has a complete outer shell with exception of helium and noble gases. (2) Representative elements of typical elements : All elements of sub-groups of the periodic table are representative of typical elements.They include metals ,non metals and metalloids.Some of the elements are paramagnetic and some are diamagnetic.These include of elements of s and p-blocks. (a) s-block elements : In...

FOOD AND NUTRITION Introduction : Food and nutrition is a field of biochemistry which deals with the nutrients and caloric requirement of the living body.It deals with the effect on growth and metabolism of the living system arising from the imbalanced diet.For instance the statistical survey data of food and nutrition showed that 30 % population was suffering from the disease of malnutrition Diseases like decayed and crocked teeth, bone deformation,lack of mental alertness and under weight were real outcome of the unbalanced food and diet. Classification : The food is required by the body to achieve three purposes. (a) Energy (b) Growth and maintenance of tissues (c) Regulation of body processes and for the sake of simplicity It is classified into six groups: (i) Carbohydrate (ii) Lipids and fat (iii) Proteins (iv) Vitamins (v) Minerals (vi) Water Elements of Nutrition : For healthy performance, each day the diet must supply the body with: A...

INDUSTRIAL PREPARATION OF HYDROGEN In industry, Hydrogen is manufactured from water,natural gas and ammonia..Methods are arranged in the order of their importance : (i) Electrolysis of Water : When electricity is passed through water containing a small amount of an electrolyte (an acid ,a base or salt) water decompose into hydrogen and oxygen.Hydrogen collects at cathode and oxygen gas, a by-product,is collected at anode. 2H2O ----------> 2H2 + O2 The gases produced are in the purest form.This process is expensive and is used to produce hydrogen where electricity is available at cheaper rates. (ii) Steam and Hydrocarbon Process : A mixture of steam and natural gas when over nickel catalyst at 900 C produces a mixture of hydrogen and carbon monoxide commonly known as Water gas, Natural gas contains about 94.60 % methane CH4 +H2O ---------- > 3H2 + CO (iii) By the action of steam on coal : When steam is passed over red hot coke at about 1000 C, a mixture of hydrogen and carbo...

MANUFACTURE OF SODIUM BICARBONATE AND SODIUM CARBONATE BY SOLVAY-PROCESS : INTRODUCTION : Solvay process was introduced by Belgian engineer Ernest Solvay (1861) for manufacture of sodium bicarbonate (baking soda) and sodium carbonate (washing soda). This process is also known as "Ammonia soda process" due to use of ammonia. DETAILS OF THE SOLVAY PROCESS : Solvay process involves the following steps: 1. AMMONIATION : Concentrated brine (sodium chloride) solution is prepared by dissolving NaCl in water.Then the brine is purified by lime-soda treatment to precipitate calcium and Magnesium as carbonate which settle down.Then the brine is pumped into a tower in which strream of ammonia gas is passed through it, the brine saturated with ammonia is called "Ammonical brine" in which CO2 is more soluble than ordinary brine. 2. CARBONATION : Carbonation involves combination of CO2 with ammonical brine. For this purpose CO2 is prepared in a skin by heating lime-stone. CaCO3 ...

Chemistry of Methane ( CH₄) : * In methane carbon atom has to combine with four hydrogen atoms therefore it undergoes SP3 hybridization and form four new SP3 hybrid orbital. * The SP3 hybrid orbital are arranged in tetragonal fashion with an angle of 109.5 C * Each SP3 hybrid orbital overlap with "S" orbital of four hydrogen atoms forming 4 sigma bonds.Thus form an orbital structure of methane. Preparation of Methane : * From Hydrolysis of Methyl Magnessium Iodide G.R : Methyl Magnessium iodide is a Grignard's reagent,it is on hydrolysis in acidic medium gives methane. * From Reducation of IODO Methane ( Methyl Iodide) : When iodo methane or methyl iodide is heated with molecular hydrogen in the presence of "Pb" as catalyst then it is reduced to methane. This catalytic reduction of iodo methane is called hydrogination. Similarly, when Iodo methane or methyl iodide is treated with Zn/HCl then it is reduced to methane by nascent hydrogen. From Sodium Acetate CH3C...