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IMPORTANT POINTS FOR QUICK REVISION Chapter 1-Periodicity of elements Atomic Size: Atomic size is measured in terms of atomic radius. Atomic radius is the distance from the centre of nucleus to the outermost shell to which electron belong. Ionisation Potential/Ionisation Energy/Ionisation Enthalpy: It is the minimum amount of energy required to remove most loosely bound electron from the valence shell of an isolated gaseous atom. Electron Affinity: It is amount of energy released when an extra electron is added to the outermost shell of an isolated gaseous atom to form an anion. Electronegativity: It the ability or capacity of an atom to attract shared pair of electrons towards itself in a covalently bonded molecule is called as electronegativity. Trend of Properties Across period and Down the Group Property Down the Group Across Period Atomic Size Increases Decreases Ionisation Potential Decreases Increases Electron Affinity Decreases Increases Electronegativity Decreases Increases Metallic Character Increases Decreases Decreases Increases Non-metallic Character Important Points For Quick Revision -Ketan.R.Thakkar 1 Chapter: -2 Chemical Bonding Chemical Bond: It is the force of attraction which holds two or more than two atoms together in a molecule is called Chemical Bond Ionic or Electrovalent Bond: - It is the electrostatic force of attraction which holds two or more than two oppositely charged ion together in a molecule Or The bond which is formed by transfer of electron from one atom to another atom is called as Ionic or Electrovalent Bond This bond is formed between metal and non-metal and it is stronger bond Covalent Bond: The bond which is formed by mutual sharing of electrons between two atoms If only one pair of electrons is shared between two atoms it will form a Single covalent bond If two pair of electrons are shared it will form a Double covalent bond If three pair of electrons are shared between two atoms it will form a Triple covalent bond Coordinate covalent bond or Coordinate Bond or Dative Bond :A bond formed when a pair of electrons is donated by one atom but shared between two bonded atoms is known as coordinate bond. This bond is also known as Dative bond. A coordinate bond is represented by a small arrow ( ). The head of the arrow points towards the electron pair acceptor atom. Moleculesand Bonding :Sr No 1 2 3 4 5 6 7 8 9 Molecule Ammonia Calcium Oxide Methane Oxygen Chlorine Magnesium Chloride Potassium Chloride Carbon tetrachloride Phosphorous tri chloride Important Points For Quick Revision -Ketan.R.Thakkar Type of Bonding Covalent Bond Ionic Bond Covalent Bond Double Covalent Bond Single Covalent Bond Ionic Bond Ionic Bond Covalent Bond Covalent Bond 2 10 11 12 13 14 15 Zinc Sulphide Ammonium ion Hydronium ion Ammonium chloride Hydrogen chloride Sodium chloride Ionic Bond Covalent and Coordinate bond Covalent and Coordinate Bond Covalent, Coordinate and Ionic Bond Polar Covalent Bond Ionic Bond ELECTRON-DOT AND CROSS DIAGRAMS Important Points For Quick Revision -Ketan.R.Thakkar 3 Chapter -3 Acids, Bases and Salts Salts:- Any compound which when dissolved in water produces positively charged ion other than H+1 and negatively charged ion other than OH-1 Or Salt is a compound formed by partial or complete replacement of H+1ion of acid by either metal or ammonium radical. Types of Salts :1) Normal Salt:- The salt which is formed by complete replacement of H+1 ion of acid by either metal or ammonium radical. 2) Acid salts:- The salt which is obtained by partial or incomplete replacement of H+1 ion of an acid by either metal or ammonium radical. 3) Basic salts :- The salt which formed by partial or incomplete replacement of OH-1 ion of base by anion. Deliquescence :- It is a process in which substance absorbs moisture from the surrounding and dissolves in it to form saturated solution is called Deliquescence and the substance is called as Deliquescent substance [The substance should be solid and compulsory to dissolve and to form saturated solution] Efflorescence: - It is the process of losing water of crystallisation either partially or completely by a hydrated substance when it is exposed to air or heat. The substance is called as efflorescent substance Water of crystallisation: - It is the number of water molecules present in a salt crystal is called water of crystallisation Hygroscopy :- Certain substances when exposed to the atmosphere at ordinary temperature absorbs moisture from the atmosphere without dissolving in it, is called as hygroscopy and the substance is called as hygroscopic substances .They are usually anhydrous solids or liquids and used as Drying agent for gases.[Substance can be either solid or liquid] pH:-It is define as negative logarithm to the base10 of hydrogen ion concentration. It is a measure of strength of hydrogen ion concentration 0 7 Strong Acidic Weak Acidic Acidic strength increases Weak Basic Neutral Important Points For Quick Revision -Ketan.R.Thakkar 14 Strong Basic Basic strength increases 4 Reactions of Laboratory Preparation of Salts:1) Zinc Sulphate :Zn(s) + H2SO4(dil) ZnSO4 (aq) +H2 ZnSO4(s) + 7H2O (liq) ZnSO4 .7H2O 2) Iron(II) Sulphate Fe(s) + H2SO4(dil) FeSO4(s) + 7H2O (liq) FeSO4 (aq) +H2 FeSO4 .7H2O 3) Copper Sulphate CuO + H2SO4(dil) CuSO4(aq) + H2O OR Cu(OH)2 + H2SO4(dil) CuSO4(aq) + H2O CuSO4 (s) + 5H2O CuSO4.5H2O 4) Lead Sulphate PbO + 2HNO3 PbCO3 + 2HNO3 Pb(NO3)2 + H2SO4(dil) Pb(NO3)2 + H2O OR Pb(NO3)2 +H2O+CO2 PbSO4 + 2HNO3 5) Lead Chloride PbO + 2HNO3 Pb(NO3)2 + H2O OR PbCO3 +2 HNO3 Pb(NO3)2 + 2HCl Pb(NO3)2 +H2O+CO2 PbCl2 + 2HNO3 OR Pb(NO3)2 +2NaCl PbCl2 + 2NaNO3 6) Lead Nitrate PbCO3 +2HNO3 Pb(NO3)2 +H2O+CO2 7) Sodium Chloride NaOH + HCl NaCl + H2O 8) Sodium sulphate NaOH (aq) +H2SO4 (aq) Na2SO4(s) + 10H2O 9) Iron (III) Chloride 2Fe(s) + 3Cl2 (g) Na2SO4(aq) + H2O Na2SO4.10H2O 2FeCl3(s) Important Points For Quick Revision -Ketan.R.Thakkar 5 Methods of preparation of salts No 1 2 3 4 5 6 Method Direct Combination/Synthesis Simple Displacement Decomposition by Acids Double decomposition/ Precipitation Neutralisation Titration Deliquescence substance Anhydrous calcium chloride Magnesium chloride Solid sodium hydroxide Solid potassium hydroxide Calcium nitrate Ferric chloride Zinc nitrate Examples FeCl3,AlCl3,ZnCl2, ZnS, PbS, CuS FeSO4.7H2O,ZnSO4.7H2O,ZnCl2,AlCl3 Pb(NO3)2, FeSO4, PbSO4,PbCl2, PbCO3, CaCO3, ZnS, PbS, CaSO4, AgCl, PbSO3,CuSO3 Pb(NO3)2, FeSO4, NaCl,KCl,NH4Cl,NaNO3,KNO3,NH4NO3, Na2SO4, K2SO4,(NH4)2SO4 Examples of Hydrated Hygroscopic substance substance . CaCl2 6H2O Concentrated sulphuric acid Ca(NO3)2.4H2O Calcium oxide CaSO4.2H2O CuSO4.5H2O FeSO4.7H2O ZnSO4.7H2O Na2CO3.10H2O Na2SO4.10H2O Dehydrating agent Concentrated sulphuric acid Anhydrous calcium chloride Solid potassium hydroxide Solid sodium hydroxide Ferric chloride Phosphorus pentoxide Silica gel Important Points For Quick Revision -Ketan.R.Thakkar 6 Chapter -4 Mole Concept and Stoichiometry Avgadro s Number:- 6.023 x 10-23 Molar volume = Gram molecular mass (GMM) Mass per litre of gas at STP Relative atomic mass (RAM) = Mass of one atom of element Mass of one atom of hydrogen Relative molecular mass (RMM) = Mass of one molecule of substance Mass of one atom of hydrogen Gram atoms = Mass in grams of element Relative atomic mass (Atomic weight) Gram molecule = Mass in grams of substance Relative molecular mass ( Molecular weight) Number of moles of an atom = Mass of element(in gram) Realtive atomic mass Vapour density = Mass of certain volume of gas Mass of same volume of hydrogen = Molar mass 2 Percentage composition of mass = Weight of the element in one molecule of substance Gram molecular weight 100 Molecular Formula = n Empirical Formula n= Molecular formula weight (Molecular weight) Empirical formula weight Important Points For Quick Revision -Ketan.R.Thakkar 7 Chapter 5 - Electrolysis Electrolysis: - The process of chemical decomposition of the substance in its aqueous or molten state by passage of electric current is called as electrolysis. Electrolytes :- The chemical substance which allows the passage of electric current in its aqueous state or molten state and is decomposed by it. Strong electrolytes: - The substances which dissociates completely in aqueous solution or molten state and allows large amount of electric current to pass through it is called as strong electrolytes. Weak electrolytes: - The substance which does not dissociate completely in its aqueous or molten state and allows small amount of electric current to pass through it is called as weak electrolytes. Non electrolytes: - The substance which in its aqueous or molten state does not allow electricity to pass through them are called as non-electrolyte. Electrode: - It is the conducting rod of a metal or graphite through which electric current enters and leaves the electrolyte is called as electrode. Anode: - It the electrode which is connected to the positive terminal of battery. The current enters the electrolyte through anode. Cathode: - It is the electrode which is connected to the negative terminal of battery. The current leaves the electrolyte through cathode. Electrolytic dissociation: - The process of separation of ions which are already present in molecule is called as electrolytic dissociation. Ionisation: - The process of formation of ions from molecules which are not present in molecules is called as ionisation. Electrochemical Series :-It is the series in which metal or non- metal are arranged in decreasing order of their tendency to lose or gain electrons. Selective or Preferential Discharge: - If two or more ions of the same charge are present in solution of an electrolyte under ideal conditions and are competing for discharge at the same electrode, one of them gets preferentially discharged. It is known as selective discharge. Important Points For Quick Revision -Ketan.R.Thakkar 8 Electroplating: - The deposition of thin but firm coating of superior metal (Ag, Ni, Cr, Au) on the surface of inferior metal (Cu, Fe, Zn) is called as electroplating. Electrolysis of molten lead bromide with inert or graphite electrode :Pb+2 + 2Br-1 PbBr2 Reaction at anode (Oxidation) Reaction at cathode (Reduction) 2Br-1 -- 2e- 2Br 2Br Br2 Pb+2 + 2e- Pb Electrolysis of acidulated water :H+1 + OH-1 H2O H+1 + Cl-1 HCl Reaction at anode (Oxidation) 4OH-1 -- 4e4OH 4OH 2H2O+O2 Reaction at cathode (Reduction) 4H+1 + 4e4H 4H 2H2 Electrolysis of Copper Sulphate Solution using Copper Electrode Cu+2 + SO4-2 CuSO4 H+1 + OH-1 H2O Reaction at anode (Oxidation) Cu -- 2e-1 Cu+2 Reaction at cathode (Reduction) Cu+2 + 2e- Cu Electroplating an article with Silver Electrolyte :- Sodium argent cyanide/Sodium silver cyanide Anode:- Pure block or rod of silver Cathode :- Article to be electroplated Reaction at anode (Oxidation) Ag -- 1e-1 Ag+1 Reaction at cathode (Reduction) Ag+1 + 1e- Ag Important Points For Quick Revision -Ketan.R.Thakkar 9 Electroplating an article with Nickel Electrolyte :- Nickel sulphate Solution/Solution containing Nickel ion Anode:- Pure block or rod of Nickel Cathode :- Article to be electroplated Reaction at anode (Oxidation) Ni -- 2e-1 Ni+2 Reaction at cathode (Reduction) Ni+2 + 2e- Ni Electrorefning of Copper Anode:- Impure copper rod Cathode :- Pure Copper rod Electrolyte :- Aqueous solution of copper sulphate Reaction at anode (Oxidation) Cu -- 2e-1 Cu+2 Reaction at cathode (Reduction) Cu+2 + 2e- Cu Electrochemical Series For metals K Ca Na Mg Al Zn Fe Pb [H] Cu Hg Ag Increasing ease of Reduction Cations are discharged at cathode by gain of electron Important Points For Quick Revision -Ketan.R.Thakkar -2 SO4 NO3-1 Cl-1 Br-1 I-1 OH-1 Increasing ease of Oxidation Anions are discharged at anode by loss of electrons 10 Strong Electrolyte Hydrochloric acid Nitric acid Sulphuric acid Potassium hydroxide Sodium hydroxide Lithium hydroxide Lead bromide Copper chloride Silver nitrate Examples of electrolytes Weak Electrolyte Acetic acid Formic acid Carbonic acid Calcium hydroxide Magnesium hydroxide Ammonium hydroxide Sodium carbonate Potassium bicarbonate Lead acetate Non electrolyte Pure distilled water Alcohol Kerosene Carbon disulphide Carbon tetrachloride Sucrose solution Glucose solution Sugar solution Difference in electricity conducted by Metal and Electrolyte Metal Electrolyte The flow of electricity is due to flow The flow of electricity is due to ions of electrons Metals both in solid and liquid state Electrolytes are good conductors only are good conductors of electricity in aqueous solution or in molten state No change of form or in composition New products are formed at the occurs during conduction of electrodes. This involves a chemical electricity. This is only physical change change For example Cu and Al wire For example-Aqueous solution of CuSO4 Important Points For Quick Revision -Ketan.R.Thakkar 11 Chapter-6 Metallurgy Metallurgy: - The branch of science which deals with large scale extraction of metal from its ore is called as metallurgy Minerals: - The compounds of different metals found in earth crust is called as minerals Ores: -Ores are those minerals from which metals can be extracted profitably is called as Ores All the ores are minerals but all minerals are not ore Gangue/Matrix: - The rocky impurities like silica, mud associated with the ore is called as Gangue/matrix Common Ores of metal Aluminium Lead Copper Bauxite Galena Copper Pyrite Al2O3.2H2O PbS CuFeS2 Cryolite Na3AlF6 Iron Haematite Fe2O3 Magnetite Fe3O4 Limonite Fe2O3.H2O Zinc Zinc blende ZnS Calamine ZnCO3 Process involved in metallurgy Ore Crushing of Ore Concentration of Ore Roasting & Calcination Froth Flotation Electromagnetic separation Gravity Separation Reduction Refining of metals Metal Important Points For Quick Revision -Ketan.R.Thakkar 12 1 2 3 Difference Between Roasting and Calcination Roasting Calcination It is a process of conversion of 1 The process of conversion of sulphide ore in to its oxide carbonate ore into its oxide The process is carried out in 2 The process is carried out in presence of air absence of air Sulphur dioxide gas is evolved 3 Carbon dioxide gas is evolved Extraction of Aluminium Extraction of aluminium from its ore Bauxite is carried out in two steps 1) Conversion of Bauxite in to Alumina 2) Electrolytic reduction of Alumina to give Aluminium (Hall Heroults Process) Conversion of Bauxite into Alumina :1) Conversion of Bauxite into Alumina (Bayer s Process) Bauxite (Al2O3.2H2O) Impurities separate (Fe2O3 & SiO2) Roasted Digested with Hot NaOH Filtered and Hydrolysis (Agitated with Al(OH)3 Al2O3 + 2NaOH 2NaAlO2 + H2O NaAlO2+ 2H2O 50-60OC Al(OH)3 + NaOH Pure Al(OH)3 Ignition 2Al(OH)3 1100 OC Al2O3 + 3H2O Pure Alumina(Al2O3) Important Points For Quick Revision -Ketan.R.Thakkar 13 2) Conversion of Alumina into Aluminium Or Electrolytic Reduction of Alumina (Hall-Heroult Process) Pure Alumina(Al2O3) Dissolved in molten cryolite (Na3AlF6) Molten mixture of Al2O3 + Na3AlF6 + CaF2 2Al2O3 4Al+3 + 6O-2 Reaction at anode (Oxidation) 6O-2 6[O]+ 12e-1 6[O] 3O2 C+ O2 CO2 Reaction at cathode (Reduction) 4Al+3 +12e-1 4Al Aluminium Significance of the substances in the extraction of Aluminium 1) Bauxite :- It is the main ore of aluminium which is contaminated with the impurities of Silica and Iron oxide 2) Sodium hydroxide :- It is used in purification of bauxite as aluminium oxide is amphoteric in nature whereas impurities as basic in nature so do not react Al2O3 + 2NaOH 2NaAlO2 + H2O 3) Cryolite:- It is added to lower the fusion temperature of electrolytic bath. The mixture melts at 900-950 0C instead of 2050 0C thus saving electrical energy 4) Cryolite and Fluorspar (CaF2) :- It enhances the conductivity of the mixture as pure alumina is almost non conductor of electricity and also acts as a solvent for electrolytic mixture. 5) Graphite :- It acts as anode .Here anode gets oxidised to carbon dioxide due to which it is continuously replaced during the electrolysis as it is consumed 6) Powdered Coke :- A layer of powdered coke sprinkled over the electrolytic mixture prevents the burning of the carbon anode in air at the point where they emerge from the bath and also prevents heat loss by radiation. Important Points For Quick Revision -Ketan.R.Thakkar 14 Alloys :- An alloy is a mixture of two or more metal or metal and a non metal fused together in molten state in a fixed proportion. Amalgam:- An amalgam is an alloy in which one of the component metal is mercury. Reasons for Alloying :1) To increase the hardness, tensile strength and resistance to electricity 2) To lower the melting point 3) To modify the appearance ,colour ,chemical reactivity and casting ability Common Alloys Name of Alloy Duralumin Brass Composition Al, Mg, Mn ,Cu Cu, Zn Bronze Cu, Sn, Zn Fuse metal Or Solder Stainless steel Pb, Sn Fe, C, Ni, Cr Properties Light, Corrosion resistant, Hard Strong, easy to cast and takes good polish Hard, Tenacious, Durable, Resistant to corrosion Low melting point and high tensile strength Resistant to corrosion, lustrous, high tensile strength Important Points For Quick Revision -Ketan.R.Thakkar Uses Making aircrafts, rockets, speed car and pressure cooker Making house hold utensils and electrical fittings Making utensils, coins ,statue Making electrical fuse and for soldering purposes Making cutlery, utensils, automobile parts 15 Chapter 7- Hydrogen Chloride and Hydrochloric acid Laboratory Preparation: Reactants: - Solid sodium chloride and Concentrated sulphuric acid Reactions: - NaCl +H2SO4 <2000C NaHSO4 +HCl KCl + H2SO4 <2000C KHSO4 + HCl Temperature:- It should be less than 200 oC as it lead to wastage of fuel, Forms a hard crust of Sodium sulphate which becomes difficult to remove and glass apparatus may develop crack Drying agent :- Concentrated sulphuric acid is used as drying agent (Other drying agents chemically combine with hydrogen chloride gas so they are not used) Collection: - It is collected by upward displacement of air as it is heavier than air (Not collected over water as it is highly soluble in water) Identification :-It produces dense white fumes when a glass rod dipped in ammonium hydroxide solution or ammonia solution is brought near to it Fountain Experiment :- The experiment demonstrate the high solubility of gas in water and also with the change in colour of litmus solution ( Blue litmus turning red) indicates the gas is acidic in nature Hydrochloric acid:- Saturated solution of hydrogen chloride gas in water is referred as hydrochloric acid. It is obtained by dissolving hydrogen chloride gas in water Back suction: - The reverse rise of water in delivery tube is called as back suction. It arises because rate of generation of gas is less as compared to the rate of absorption of gas thus due to pressure difference water rises up in delivery tube and causes back suction Funnel arrangement:- Inverted funnel arrangement is used to prevent /minimise back suction and also it provides larger surface area for the absorption of the gas. Constant Boiling mixture:- A mixture which boils without any change in its composition is called as constant boiling mixture or azeotrope mixture. At 1100C it forms constant boiling mixture Important Points For Quick Revision -Ketan.R.Thakkar 16 Chemical Properties :1) Reaction with metals Metal 2Na Ca Mg Zn Fe + Acid/Gas + 2HCl + 2HCl + 2HCl + 2HCl + 2HCl Metal Chloride 2 NaCl CaCl2 MgCl2 ZnCl2 FeCl2 + + + + + + Hydrogen H2 H2 H2 H2 H2 2) Reaction with metallic oxide :Metal Oxide + Acid /Gas Metal Chloride + Water Na2O + 2HCl 2NaCl + H2O CaO + 2HCl CaCl2 + H2O CuO + 2HCl CuCl2 + H2O PbO + 2HCl PbCl2 + H2O 3) Reaction with metallic hydroxides :Metallic + Hydrochlolric Hydroxide Acid ( Dilute) NH4OH + HCl Al(OH)3 + 3HCl Zn(OH)2 + 2HCl Cu(OH)2 + 2HCl Metal Chloride NH4Cl AlCl3 ZnCl2 CuCl2 + Water + + + + H2O 3H2O 2H2O 2H2O 4) Reaction with metallic carbonates/bicarbonates Metallic carbonate / + Hydrochloric Metal + water Bicarbonate Acid (Dilute) Chloride Na2CO3 + 2HCl 2NaCl + H2O NaHCO3 + HCl NaCl + H2O CaCO3 + 2HCl CaCl2 + H2O CuCO3 + 2HCl CuCl2 + H2O 5) Reaction with metallic sulphides Metallic + Hydrochloric Sulphide Acid (Dilute) Na2S + 2HCl FeS + 2HCl Important Points For Quick Revision -Ketan.R.Thakkar Metal Chloride 2NaCl FeCl2 + Carbon dioxide + CO2 + CO2 + CO2 + CO2 + Hydrogen Sulphide + H2S + H2S 17 6) Reaction with metallic sulphites and bisulphites Metallic Sulphites / + Hydrochloric Metal + water + Sulphur Bisulphites Acid (Dilute) Chloride dioxide Na2SO3 + 2HCl 2NaCl + H2O + SO2 NaHSO3 + HCl NaCl + H2O + SO2 7) Reaction with metallic nitrates (Test for Dilute Hydrochloric acid) Pb(NO3)2 + 2HCl PbCl2 + 2HNO3 Lead (Dilute) Lead Chloride Nitrate (White ppt) AgNO3 Silver Nitrate AgCl + + HCl (Dilute) AgCl Silver Chloride (White ppt) 2NH4OH 8) Reaction with Oxidizing agent Oxidizing + Hydrochloric Agent Acid ( Conc) MnO2 + HNO3 [Ag(NH3)2]Cl + 2H2O Diammine silver Chloride (Soluble) heat + 4HCl (Conc) Important Points For Quick Revision -Ketan.R.Thakkar Salt + water + Chlorine MnCl2 + 2H2O + Cl2 18 Chapter -8 Ammonia Laboratory Preparation :Reactants :- Solid ammonium chloride(2part) and Slaked lime (Calcium hydroxide)( 3part). Higher ratio of slaked lime is taken in order to counteract the loss of ammonium chloride due to sublimation. Slaked lime is preferred over other alkali as it is cheaper and not deliquescent like NaOH or KOH, Reaction:- 2NH4Cl + Ca(OH)2 CaCl2 + 2H2O + 2NH3 Drying agent:- Calcium oxide (Quick lime) as it is basic in nature will not react with ammonia where as other drying agents chemically combine with ammonia gas. Collection:- By downward displacement of air as it is lighter than air and not collected over water as it is highly soluble in water. Reaction of metal nitride with warm water Mg3N2 + 6H2O 3Mg(OH)2 + 2NH3 AlN + 3H2O Al(OH)3 + NH3 Industrial Preparation of Ammonia Name of the Process Haber s Process Reactants Hydrogen (From Bosch Process) Nitrogen (By liquefaction of air ) Pressure 200-900atm pressure Temperature 4500C Catalyst and Promoter Finely divided Iron and Molybdenum Reaction N2(g) + 3H2(g) 2NH3(g) + Heat Recovery of Ammonia By liquefaction (as it can be liquefied easily at -330C from unreacted Nitrogen at this temperature nitrogen and hydrogen will not and Hydrogen liquefy OR By dissolving in water (as ammonia is highly soluble in water whereas nitrogen and hydrogen are practically insoluble) Important Points For Quick Revision -Ketan.R.Thakkar 19 Fountain Experiment :- The experiment demonstrate the high solubility of gas in water and also with the change in colour of litmus solution ( Red litmus turning Blue) indicates the gas is alkaline/Basic in nature Chemical Properties 1) Reaction with oxygen :- Ammonia neither burns nor support burning but in an atmosphere of oxygen with yellowish flame to give nitrogen and water vapour 4NH3 + 3O2 2N2 + 6H2O 2) Reaction with Oxygen in presence of Catalyst :- Ammonia is oxidised to colourless nitric oxide which further oxidised to Nitrogen dioxide (Reddish brown gas) and catalyst continues to glow due to exothermic nature of reaction 4NH3 + 5O2 Pt /500*C 4NO +6H2O + Heat 2NO +O2 2NO2 3) Reducing properties of Ammonia :a) Reaction with chlorine :- Ammonia reduces chlorine to hydrogen chloride 2NH3+3Cl2 6HCl+N2(g) b) Reaction with excess of chlorine:- Ammonia reacts with excess of chlorine to give yellow coloured explosive liquid Nitrogen trichloride NH3 +3Cl2 3HCl + NCl3 (excess) Nitrogen trichloride c) Reaction with excess of Ammonia:- When ammonia gas is in excess as compared to chlorine gas, initially it reacts to form hydrogen chloride .Thus chlorine gas gets reduced to hydrogen chloride. The hydrogen chloride thus formed further combines with excess of ammonia to form dense white fumes of ammonium chloride. 2NH3+3Cl2 6NH3+6HCl 8NH3 (excess) + 3Cl2 6HCl+N2(g) 6NH4Cl 6NH4Cl+ N2 (g) Important Points For Quick Revision -Ketan.R.Thakkar 20 d) Reaction with metallic oxide:- Certain metallic oxide gets reduced to metal when heated with ammonia 2NH3 + 3CuO 3Cu + 3H2O + N2 4) Basic character of Ammonia :- Ammonia or ammonia solution (Ammonium hydroxide) reacts with acid to form corresponding salt and water. NH3+ HCl NH4Cl 2NH3 +H2SO4 (NH4)2SO4 NH3 +HNO3 NH4NO3 NH4OH + HCl NH4Cl +H2O 2NH4OH + H2SO4 (NH4)2SO4 +H2O NH4OH +HNO3 NH4NO3 + H2O Liquid ammonia is used as a refrigerant in ice plants as well as in cold storages due to following properties As liquid ammonia is highly volatile It has high specific latent heat of vaporization It can be liquefied easily under pressure at room temperature NH3(liquid) NH3(g) 57000cals As during evaporation of ammonia large amount of energy is absorbed from the surrounding and water gets converted in to ice. Important Points For Quick Revision -Ketan.R.Thakkar 21 Chapter -9 Nitric Acid Laboratory Preparation : Reactants :- Solid Sodium or Potassium nitrate and Concentrated Sulphuric acid ( Both reactants in equal Part) Reactions: - NaNO3+H2SO4 <200 C NaHSO4 +HNO3 0 KNO3 + H2SO4 <2000C KHSO4 +HNO3 Collection:- The vapours of nitric acid are condensed and collected in water cooled receiver The complete apparatus is made up of glass as nitric acid vapours are corrosive in nature can attack rubber or cork Concentrated hydrochloric acid is not used in place of concentrated sulphuric acid as hydrochloric acid is volatile acid may come out along with vapours of nitric acid The temperature of reaction mixture should be less than 2000C as 1) It leads to wastage of fuel, 2) May lead to decomposition of nitric acid 3) Forms a hard crust of Sodium sulphate which becomes difficult to remove 4) Glass apparatus may develop crack Pure Nitric acid is colourless but acid obtained in laboratory is slightly yellow colour due to dissolution of nitrogen dioxide in it which is produced by thermal decomposition of nitric acid 4HNO3 2H2O +4NO2 +O2 The yellow coloured can be removed by passing dry air or by addition of water to it Nitric acid cannot be concentrated above 68% by distillation as it forms constant boiling mixture Industrial Preparation of Nitric Acid :Name of the Process Ostwald s Process Reactants Ammonia and air Catalyst Platinum Reactions 4NH3 +5O2 Pt/800 C 4NO + 6H2O + Heat 2NO(g) +O2(g) 50 C 2NO2(g) 4NO2 + 2H2O +O2 4HNO3 0 0 Important Points For Quick Revision -Ketan.R.Thakkar 22 Chemical Properties :1) Reaction with metals :Generally nitric acid whether concentrated or dilute acts as oxidising agent so when reacted with metal oxidises hydrogen to water so it will not produce hydrogen gas when reacted with metal Mg + 2HNO3 (1% dilute) Mn + 2HNO3 (1% dilute) Mg(NO3)2 + H2 Mn(NO3)2 + H2 2) Reaction with metallic oxide :Metal Oxide + Nitric Acid Metal Nitrate CuO + 2HNO3 Cu(NO3)2 PbO + 2HNO3 Pb(NO3)2 3) Reaction with metallic hydroxides :Metallic + Nitric Acid Metal Hydroxide (Dilute) Nitrate NH4OH + HNO3 NH4NO3 Cu(OH)2 + 2HNO3 Cu(NO3)2 + Water + H2O + H2O + Water + H2O + 2H2O 4) Reaction with metallic carbonates/bicarbonates Metallic carbonate / +Nitric acid Metal + water + Carbon Bicarbonate (Dilute) Nitrate dioxide Na2CO3 + 2HNO3 2NaNO3 + H2O + CO2 NaHCO3 + HNO3 NaNO3 + H2O + CO2 CaCO3 + 2HNO3 Ca(NO3)2 + H2O + CO2 CuCO3 + 2HNO3 Cu(NO3)2 + H2O + CO2 5) Reaction with metallic sulphites and bisulphites Metallic Sulphites / +Nitric acid Metal + water + Bisulphites (Dilute) Nitrate Na2SO3 + 2HNO3 2NaNO3 + H2O + NaHSO3 + HNO3 NaNO3 + H2O + Important Points For Quick Revision -Ketan.R.Thakkar Sulphur dioxide SO2 SO2 23 Nitric acid as Oxidizing agent:Concentrated as well as dilute nitric acid acts as oxidizing agent as it decomposes to give nascent oxygen 2HNO3 (Conc) 2NO2 + H2O + [O] 2HNO3 (Dilute) 2NO +H2O + 3[O] Reaction with Sulphur:- Sulphur gets oxidised to sulphuric acid when reacted with concentrated nitric acid S + 6HNO3 H2SO4 + 6NO2 + 2H2O (Conc) Reaction with Carbon :- Carbon gets oxidised to carbon dioxide when reacted with concentrated nitric acid C + 4HNO3 CO2+4NO2 +2H2O (Conc) Reaction with Copper:- Copper gets oxidised to copper nitrate with release of Nitric oxide gas( when reacted with dilute ) and Nitrogen dioxide ( when reacted with concentrated) 3 Cu + 8HNO3 3Cu(NO3)2 + 2NO + 4H2O (Dilute) Cu + 4HNO3 Cu(NO3)2 + 2NO2 + 2H2O (Conc) Test for Nitric acid:1) On heating produces reddish brown fumes 2) Answers brown ring test 3) On heating with copper turning produces reddish brown gas Action of heat on nitrate:1) The nitrates of Sodium and Potassium when heated undergoes decomposition to liberate metal nitrite and Oxygen gas 2) Other metal nitrates of Calcium till Copper forms metal nitrate and releases brown colour Nitrogen dioxide gas and colourless Oxygen gas 3) Nitrate of Mercury and Silver decomposes to give corresponding free metal with liberation reddish brown Nitrogen dioxide and colourless Oxygen gas 4) Ammonium Nitrate which decomposes to gives dinitrogen oxide (N2O) and water vapour. As both the products are in gaseous state it do not leave any residue Important Points For Quick Revision -Ketan.R.Thakkar 24 Chapter -10 Sulphuric acid Commonly known as Oil of vitriol as obtained as oily viscous liquid on heating green vitriol (Hydrated ferrous sulphate) Industrial Preparation Name of the Process Contact Process Reactants Sulphur or sulphide containing ore Catalyst Platinum Or Vanadium pentoxide Reactions Roasting Oxidation of sulpur to sulphur dioxide S +O2 SO2 4FeS2 +11O2 2Fe2O3 + 8SO2 Oxidation of sulphur dioxide 2SO2 +O2 2SO3 Pt/V O 2 5 to sulphur trioxide Conversion of sulphur trioxide to oleum Dilution of Oleum H2SO4 +SO3 H2S2O7 + H2O 2H2S2O7 (Oleum) 2H2SO4 Platinum is replaced with vanadium pentoxide as platinum gets poisoned impurities of arsenic oxide and dust particles and The direct absorption of sulphur trioxide in sulphuric acid is necessary because reaction between sulphur trioxide and water results in a mist of sulphuric acid filling the factory. Dilution of sulphuric acid is an exothermic process hence always care should be taken to add acid to water not water to acid as heat release during dilution may cause acid to acid to spill out and can lead to damage Chemical Properties 1) Reaction with metals Metal + Acid (Dilute) 2Na + 2H2SO4 Ca + H2SO4 Mg + H2SO4 Zn + H2SO4 Fe + H2SO4 Metal Sulphate + 2Na2SO4 + CaSO4 + Mg SO4 + Zn SO4 + Fe SO4 + Important Points For Quick Revision -Ketan.R.Thakkar Hydrogen H2 H2 H2 H2 H2 25 2) Reaction with metallic oxide :Metal Oxide + Acid (Dilute) Na2O + H2SO4 CaO + H2SO4 CuO + H2SO4 Metal Sulphate + Na2SO4 + CaSO4 + CuSO4 + Water H2O H2O H2O 3) Reaction with metallic hydroxides :Metallic + Sulphuric Metal Hydroxide Acid ( Dilute) Sulphate 2NH4OH + H2SO4 (NH4)2SO4 Zn(OH)2 + H2SO4 ZnSO4 Cu(OH)2 + H2SO4 CuSO4 + H2O + 2H2O + 2H2O 4) Reaction with metallic carbonates/bicarbonates Metallic carbonate / Sulphuric Metal Bicarbonate Acid (Dilute) Sulphate Na2CO3 + 2 H2SO4 Na2SO4 NaHCO3 + H2SO4 Na2SO4 CaCO3 + H2SO4 CaSO4 CuCO3 + H2SO4 CuSO4 + water + Carbon dioxide + H2O + CO2 + H2O + CO2 + H2O + CO2 + H2O + CO2 5) Reaction with metallic sulphides Metallic + Sulphuric Sulphide Acid (Dilute) Na2S + 2 H2SO4 FeS + 2 H2SO4 Metal Sulphate Na2SO4 FeSO4 + Water + + + Hydrogen Sulphide H2S H2S 6) Reaction with metallic sulphites and bisulphites Metallic Sulphites / + Sulphuric Metal + water + Sulphur Bisulphites Acid (Dilute) Sulphate dioxide Na2SO3 + H2SO4 2Na2SO4 + H2O + SO2 NaHSO3 + H2SO4 Na2SO4 + H2O + SO2 Important Points For Quick Revision -Ketan.R.Thakkar 26 Reaction as Oxidising Agent :Reaction with Carbon:- Concentrated sulphuric acid oxidises carbon to carbon dioxide C + 2H2SO4 CO2 + SO2 H2O (Conc) Reaction with Sulphur :- Concentrated sulphuric acid oxidises sulphur to sulphur dioxide S + 2H2SO4 3SO2 + 2H2O (Conc) Reaction as Dehydrating agent Dehydrating agent is a substance which removes element of water i.e. hydrogen and oxygen from the substance and brings out chemical change is called as Dehydrating agent. Concentrated sulphuric acid has strong affinity for water which accounts for its dehydrating character CuSO4 * 5H2O + H2SO4 CuSO4 + [5H2O +H2SO4] Blue coloured hydrated (Conc) White powdery mass Copper sulphate anhydrous copper sulphate C12H22O11 + White crystalline H2SO4 (Conc) 12C + [11H2O +H2SO4] Black porous Mass of carbon Reaction as Non-volatile acid :In comparison with hydrochloric acid and nitric acid sulphuric acid has higher boiling point hence it acts a non volatile or less volatile acid KNO3 + H2SO4 KHSO4 + HNO3 NaNO3 + H2SO4 NaHSO4 + HNO3 NaCl + H2SO4 NaHSO4 + HCl KCl+ H2SO4 KHSO4 + HCl Important Points For Quick Revision -Ketan.R.Thakkar 27 Chapter -11 Organic Chemistry Catenation:- It is the property by virtue of which carbon shows a tendency to form a bond with other carbon atom to form either long chains, branched chain or ring structure. Isomerism:- The phenomenon in which compounds have same molecular formula but different physical and chemical properties is known as Isomerism and the compounds possessing this properties are called as Isomers. Hydrocarbon:- Compounds which are made up of carbon and hydrogen only are called as Hydrocarbon. Homologous Series:-It is a group of organic compounds having similar structure, similar chemical properties in which successive members differ from one another by -CH2 . Functional Group:- It is an atom or group of atom that defines the structure or the properties of particular class of organic compound. No 1 IUPAC Name of Compound Methane Structural Formula of Compound H H C H H 2 Ethane H 3 C C H H H H H H C C C H H H H H H H H C C C C H H H H H H C C H H C n-Butane H 5 H Propane H 4 H 2-methyl propane Isobutane (Common name) H H H C H H H H Important Points For Quick Revision -Ketan.R.Thakkar 28 6 n-Pentane H H H H H C C C C C H H H H H 7 2-methyl butane Isopentane (Common name) H C H H H H H H H C C C H H H C H H H H 8 2,3-dimethyl propane Neopentane (Common name) H C H H H H C C C H H H H C H H 9 10 Ethene Ethylene (Common name) Propene 12 15 16 But-1-ene Or 1-Butene But-2-ene Or 2-Butene Pent-1-ene Or 1-pentene Pent-2-ene Or 2-Pentene H C H H H C H C C C H H H 11 H H H H H H C C C C H H H H H H C C C C H H H H H H H H H H H H H C C C C C H H H H H H H H C C C C C H H H H H 17 Ethyne Important Points For Quick Revision -Ketan.R.Thakkar H C C H 29 18 H Propyne H 19 C C C But-1-yne C H H H H C C C H 20 But-2-yne Or 2-butyne H C C C C H 21 22 Pent-1-yne Or 1-pentyne Pent-2-yne Or 2-pentyne H C H H H C C C H H H C H C C C H 24 H H H H H H H H H H H C C H H H H Chloro methane H C Cl H 25 H H C C H H Bromo ethane H 26 H H H C C C H H H H H H C C C 1-iodo propane H 27 2-iodopropane H H 28 1-bromo butane H Important Points For Quick Revision -Ketan.R.Thakkar Br I I H H H H H H C C C C H H H Br H 30 29 2-bromo butane H H H H C C C C H H Br H H 30 2-bromo-2-methyl propane H Br H C C C H H H C H H H H H 31 1-fluoro pentane H 32 H H H H H C C C C C H H 3-fluoropentane H 34 H H H H H H H C C C C C H H H H F H H H H C C C C C H H F H H 2-fluoropentane H 33 H F H H H H Methanol H C OH H 35 Ethanol H H H C C H 36 37 38 Propan-1-ol Or 1-Propanol Propan-2-ol Or 2-Propanol Butan-1-ol Or 1-Butanol Important Points For Quick Revision -Ketan.R.Thakkar H H H H OH H H H H C C C H H H H H H C C C H OH H OH H H H H C C C C H H H H OH 31 39 40 41 42 Butan-2-ol Or 2-Butanol Pentan-1-ol Or 1-pentanol Pentan-2-ol Or 2-pentanol Pentan-3-ol Or 3-pentanol 43 Methanal 44 Ethanal H H H H C C C C H H H H H H H H H C C C C C H H H H H H H H H C C C C C H H OH H H H H H H H C C C C C H H OH H H H H H H Propanal H 46 Butanal H 47 Pentanal H 48 OH H H H H H H C H O C C O H 45 OH H H H C C C H H H H H H C C C C H H H H H H H H C C C C C H H H H O H H O O O Methanoic acid H C O 49 H Ethanoic acid H C C H O Important Points For Quick Revision -Ketan.R.Thakkar O H 32 50 H 51 Butanoic acid H 52 Pentanoic acid H 53 H H C C C H H H H O C C Propanoic acid Ethyl ethanoate O H H C H H H H C C C C C O H H H H H O H H C C H H C C H O H O H H H H C O O H H Substitution Reaction :- The reaction in which one or more than one hydrogen atom of alkane gets replaced or substituted by an atom or group of atom is known as Substitution Reaction Halogenation :- The reaction in which one or more than one hydrogen atom of alkane is replaced by halogen is called as halogenation reaction. Dehydration :-Dehydration means removal of water molecule from the substance Dehydrohalogenation :- Dehydrohalogenation means removal of hydrogen as well as halogen from a molecule Addition Reaction :-The reactions in which the addition of reaction takes place in unsaturated hydrocarbon to form saturated hydrocarbon is called as addition reaction Denatured Alcohol :- Ethyl alcohol is a part of alcoholic beverages and is also used as a solvent in the industries In order to make it unfit for drinking certain poisonous substances like Pyridine, Methyl alcohol and Copper sulphate is added to it. It is called as Denatured alcohol and the process is called as Denaturing. Important Points For Quick Revision -Ketan.R.Thakkar 33 Spurious Alcohol :- It is prepared either by diluting the denatured alcohol with water and then adding necessary colour and flavours or by fermenting jaggery and distilling it under unhygienic conditions. Alcohols obtained by this method is impure and contains impurities like methyl alcohol and acetaldehyde which can lead to blindness or liver damage or even death also. Glacial Acetic acid :-Acetic acid freezes at 16.50C.In cold conditions crystallisation of acetic acid may take place forming an icy mass due to which it is called as Glacial Acetic acid. Chemical Reactions:Alkanes:1) By decarboxylation of Sodium Salt of carboxylic acid 2) From alkyl halide:- Important Points For Quick Revision -Ketan.R.Thakkar 34 3) Combustion :- 4) Chlorination Of Methane Important Points For Quick Revision -Ketan.R.Thakkar 35 5) Chlorination Of Ethane :- Alkenes :1) Dehydration of alcohol 2) Dehydrohalogenation of alkyl halide 3) Addition of Hydrogen:- Important Points For Quick Revision -Ketan.R.Thakkar 36 4) Addition of Chlorine:- 5) Addition of Bromine (Test for Unsaturation) Alkynes:1) Action of hot water on calcium Carbide:- 2) By dehydrohalogenation of 1,2 -dibromo ethane Important Points For Quick Revision -Ketan.R.Thakkar 37 3) Addition of Hydrogen:- 4) Addition of chlorine :- Important Points For Quick Revision -Ketan.R.Thakkar 38 6) Addition of Bromine in carbon Tetra chloride :- Ethyl Alcohol (Ethanol) :1) By alkalis hydrolysis of Ethyl bromide:- 2) Combustion:- 3) Reaction with sodium metal 4) Reaction with acetic acid (Esterification) Important Points For Quick Revision -Ketan.R.Thakkar 39 5) Dehydration of alcohol:- Acetic acid :1) Action of alkali:- 2) Action of alcohol(Esterification) Important Points For Quick Revision -Ketan.R.Thakkar 40
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