Electronic configuration : 27 Co [ Ar ] 3 d 7 4 s2 Electronic configuration : Co 3 + [ Ar ] 3 d6 4s0 4p0
HSC Chemistry Preparation Tips Part - II
12thChemistryPreparation Tips www . ednexa . com
Chemistry Section – IUnit Unit Max. MarksNo. Marks with Option 01 Solid State 4 6 02 Solutions and Colligative Properties 5 7 03 Chemical Thermodynamics and Energetics 6 8 04 Electrochemistry 5 7 05 Chemical Kinetics 4 6 06 General Principles and Processes of Isolation of 3 5 Elements 07 P – Block Elements 8 10 Total 35 49 www . ednexa . com
Chemistry Section – IIUnit Unit Max. MarksNo. Marks with Option 08 d & f – Block Elements 5 6 09 Co-ordination Compounds 3 4 10 Halogen Derivatives of Alkanes ( & Arenes) 4 6 11 Alcohols, Phenols & Ethers 4 6 12 Aldehydes, Ketones & Carboxylic acids 5 7 13 Organic Compounds Containing Nitrogen 4 6 14 Biomolecules 4 6 15 Polymers 3 4 16 Chemistry in Everyday Life 3 4 Total 35 49 www . ednexa . com
Paper Format for Section I & II [ 35 marks each ]Q – 1 ] Select and write most appropriate answer from the givenalternative for each sub – question. Q – 2 ] Answer any six [ out of eight ] of the following [ 12 ]Q – 3 ] Answer any three [ out of four ] of the following Q – 4 ] Answer any one [ out of two ] of the following  www . ednexa . com
1 – Mark Questions -Definition / Statement / Objective Questions2 – Mark QuestionsBig structures of last two topicsTwo step conversion, Polymerization processesDifference - 4 points ( example No Mark ) / Distinguish by reactionShort Notes, Salient Features of Theory ( 4 points )Relation between ΔH & ΔU etcDerivations / Laws of electrolysisStructures of oxides of Nitrogen / www . ednexa . com
2 – Mark QuestionsMfg. Processes ( Haber’s Process for ammonia/ Contact Process)Allotropes of P or SOxy – acids of chlorineDefects in crystal / limitations / Rault’s law / DiagramsResonating structures / Electronic Configurations2 – point answers / Isomerism, Naming of co – ordination compoundsNumericals3 – Mark QuestionsABC type crystal structuresLaws and DerivationsDaniel, Cell SHE, Calomel Electrode, Lead Accumulator3 – point answers / Reaction mechanism / SN1, SN2, Optical activityMulti step reactions ( balancing not required ) / Methods of preparationNumericals - Calculations in same units throughout www . ednexa . com
12th Chemistry8 ] d - f BlockElements www . ednexa . com
d – Block Elements :- The atoms of the elements in which the last electron enters thed – orbital of penultimate ( last but one ) energy level are known as d – block elements.This indicates that in these elements, last two shells are incompletely filled.
Electronic Configuration of first ( 3d ) Transition Series ( 21 Sc – 30 Zn )[ Ar ] 3d 1 – 10 4 s 1 – 2 www . ednexa . com
Oxidation States of first transition series www . ednexa . com
Electronic configuration of lanthanides :- www . ednexa . com
Electronic configuration of lanthanides :- www . ednexa . com
Lanthanide contraction : - Lanthanide contraction is a term used in chemistry todescribe different but closely related concepts associated with smaller than expectedatomic radii of the elements in the lanthanide series.Definition :- The decrease in the atomic and ionic radii of the lanthanide elementswith increasing atomic number is known as lanthanide contraction. Thus, the firstelement lanthanum has the largest, while the last element lutetium has the smallestradius among these elements. www . ednexa . com
12th Chemistry9 ] Co - ordinationCompounds www . ednexa . com
Isomerism in Coordination Compounds www . ednexa . com
Stereoisomerism in metal complexes with coordination number 6.Stereoisomerism in metal complexes with coordination number 6( octahedral complex ) of the type [ M a4 b2 ] n±
Stereoisomerism in metal complexes with coordination number 6.Stereoisomerism in metal complexes with coordination number 6( octahedral complex ) of the type [ M a3 b3 ] n±
Stereoisomerism in metal complexes with coordination number 6.Stereoisomerism in metal complexes with coordination number 6( octahedral complex ) of the type [ M a3 b3 ] n±For example, consider a complex [ Cr ( NH3 ) 3 Cl 3 ]. The structures of cis and transisomers are
Structure of complex compounds based on valence bond theoryE ] Structure of Hexaamminecobalt (III) ion, [ CO ( NH3 ) 6 ] 3 +1.Hexaamminecobalt ( III ) ion, [ CO ( NH3 ) 6 ] 3 + is a cationic complex, oxidation stateof Co is +3 and CN = 6Electronic configuration : 27Co [ Ar ] 3 d7 4 s2Electronic configuration : Co 3 + [ Ar ] 3 d6 4s0 4p0NH3 is a strong ligand, due to spin pairing effect, all the four unpaired electrons in3d orbital are paired giving two vacant 3d orbitals.
Structure of complex compounds based on valence bond theoryE ] Structure of Hexaamminecobalt (III) ion, [ CO ( NH3 ) 6 ] 3 +The coordination number is 6, Co 3 + ion gets six vacant orbitals by hybridisation of two3d vacant orbitals, one 4s and three 4p orbitals forming six d2sp3 hybrid orbitals givingoctahedral geometry. It is an inner complex.6 lone pairs of electrons from 6NH3 ligands areaccommodated in the six vacant d2sp3 hybrid orbitals.The six hybrid orbitals of Co 3 + overlap withfilled orbitals of NH3 forming 6 coordinate bondsgiving octahedral geometry to the complex.
Structure of complex compounds based on valence bond theoryE ] Structure of Hexaamminecobalt (III) ion, [ CO ( NH3 ) 6 ] 3 +Geometry of complex : Hexaamminecobalt ( III ) ion has a octahedral geometry dueto d2sp3 hybridisation.Magnetic property : Hexaamminecobalt ( III ) ion has no unpaired electrons. Hencethe complex is diamagnetic. (Magnetic moment, μ = 0 )Effect of ligands : Ammonia ligands causes 3d electrons to be shifted to 3d – orbitalsso that all the ten electrons are paired up in 3d – orbitals.
12th ChemistryNomenclature : Common – IUPACMethods of preparation / Name ReactionsChemical Properties / Action of different reagentsPhysical PropertiesReaction Mechanism / Effect of SubstituentResonating StructuresIntext & Exercise Question - MCQ’SExceptional Questions www . ednexa . com
Exceptional QuestionsWhat is hydride shift ? Consider the following reaction : 3 – methylbutan –2 – ol heated with Hi to form 2 – iodo – 2 – methylbutane ( and not 2 – iodo –3 – methylbutane ). This can be explained on the basis of hydride shift. www . ednexa . com
Exceptional QuestionsWhat is hydride shift ? www . ednexa . com
Exceptional QuestionsSecondary carbocation rearranges to a more stable tertiary carbocation by ahydride ion shift. Nucleophile P ion attacks tertiary carbocation to givetertiary alkyl iodide. www . ednexa . com
Exceptional QuestionsPhenol is therefore ortho and para directing.These resonance structures (canonical forms) have negative charge atortho and para positions as shown above. Hence phenol giveselectrophilic substitution reactions at ortho or para or at both thepositions but never at meta positions. Phenol is therefore ortho andpara directing. www . ednexa . com
Exceptional QuestionsThe ortho and para nitrophenol can be separated by steam distillation.O – nitrophenol is steam volatile due to intramolecular hydrogen bondingwhile p – nitrophenol is less volatile due to intermolecular hydrogen bondingwhich causes the association of molecules. www . ednexa . com
12th Chemistry14 ] Biomolecules15 ] Polymers16 ] Chemistry inEvery Day Life www . ednexa . com
12th ChemistryClassification of carbohydrates, Theory, Definitions, StructuresDifferent classes of drugs, Uses, Side effectsPolymers, Classification, Methods of preparation, UsesReaction of glucose, Pyranose, Fructanose Structures.Intext & Exercise Question - MCQ’SExceptional Questions
Peptide linkage formationThe structure of proteins show that large number of α - amino acid molecules arelinked to one another through peptide ( – CO – NH – ) linkage.The peptide linkage is formed by elimination of water molecule from the amino( – NH2 ) group of one α – ammo acid molecule and the – carboxylic ( – COOH )group of the next neighbouring α - amino acid molecule.These carboxylic ( – COOH ) and amino ( – NH2 ) groups undergo condensationwith other α – amino acids. Many peptide linkages thus formed are called polypeptide.If the molecular weight of such peptides is up to 10,000 then, it is known aspolypeptide and those having molecular weight above 10,000 are known as protein.
VitaminsSome important Vitamins, their Sources and their Deficiency DiseasesNo Name of Vitamines Sources Deficiency diseases .1. Vitamin A Fish liver oil, carrots, butter Xerophthalmia ( hardening of cornea of eye ) and milk Night blindness2. Vitamin B1 Yeast, milk, green Beri beri ( loss of appetite, retarded growth ) ( Thiamine ) vegetables and cereals3. Vitamin B2 Milk, eggwhite, liver, Cheilosis ( fissuring at corners of mouth and lips ( Riboflavin ) kidney ), digestive disorders and burning sensation of the skin.4. Vitamin B6 Yeast, milk, egg yolk, Convulsions ( Pyridoxine ) cereals and grams5. Vitamin B12 Meat, fish, egg and curd Pernicious anaemia ( RBC deficient in haemoglobin )6. Vitamin C Citrus fruits, amla and Scurvy ( bleeding gums ) ( Ascorbic acid ) green leafy vegetables7. Vitamin D Exposure to sunlight, fish Rickets (bone deformities in children ) and egg yolk And osteomalacia ( soft bones and joint pain in adults )8. Vitamin E Vegetable oils like wheat Increased fragility of RBCs and muscular germ oil, sunflower oil, etc. weakness9. Vitamin K Green leafy vegetables Increased blood clotting time
Preparation of some important addition polymersPolyacrylonitrile ( PAN or Orlon ) : -The addition polymerization of acrylonitrile inpresence of a peroxide catalyst leads to the formationof polyacrylonitrile.Polyacrylonitrile is used as a substitute for wool inmaking commercial fibres as orlon or acrilan. www . ednexa . com
Antiseptics : The chemical substances which either kill or prevent the growth ofmicro-organisms are called antiseptics. They are safe to be applied on to the livingtissues. e.g. Dettol, iodine, iodoform, boric acid etc.General uses of antiseptics :These are not harmful to living tissues and can be safelyapplied to wounds, cuts, ulcers and diseased skin surfacesThese are used to reduce odors, resulting from bacterialdecomposition of the body or in mouth.Therefore they are mixed with face powders, deodorantsand breath purifiers.These are used in antiseptic cream like soframycin andfuracin. www . ednexa . com
Examples of AntisepticsPhenol : They are used for dressing of small wounds. It causes severe burns,hence other phenolic compounds are used.Dettol : It is solution of chloro - xylenol isused in antiseptic cream and for disinfectingsurgical instruments.Bithional : It is a bacteriostatic agent (inhibits thegrowth of micro organisms), used as an agriculturalfungicide. It is used as an anti-infective in deodorants,shampoos & surgical soaps. lt can cause skin allergywhen exposed sunlight hence not used in cosmetics. www . ednexa . com
Examples of AntisepticsIodine ( I2) : Tincture of iodine is used as a topical antiseptic to kill bacteria. It isalso used in cleaning wounds and sterilizing skin before surgery. It is also used fordisinfection of water, air and sanitization of food utensils.Iodoform ( CHI3 ): It is used as an external antiseptic for wounds.Boric acid ( H3BO3 ) : It is a mild antiseptic, used by swimmers as ear drops todestroy fungal growth. It is also used for eyewash and also as a food preservativeHydrogen peroxide : It is used as a mild antiseptic, for cleaning ears, sterilizingsurgical or medical instruments. It is also used in treating skin spots, killing thefungus, dental hygiene and for avoiding contagious diseases. It is used asgermicidal due to release or nascent oxygen. www . ednexa . com
Cleansing agents : Soaps and detergents.Mechanism of cleansing action of soaps and detergents : -Soap and detergents have two parts, a long chain of hydrocarbon tail soluble in oiland other part (head) soluble in water.When soap is added to an oily part of cloth or vessel, the hydrocarbon part of soapdissolves in oil and ionic end of soap dissolves in water.The soap molecules form micelles where one of the molecules is towards the oildroplet while ionic end faces out side.This results in an emulsion in water. The soap micelle assist in dissolving the dirt inwater, thus we can wash our clothes. www . ednexa . com