Carbon and its Compounds PDF - Shobhit Nirwan

*UPDATED* For 2022-23 Boards Exam SHOBHIT NIRWAN's DESIGNED CARBON AND ITS COMPOUNDS NOTES  Covalent Bond - Examples of covalent Bonding - formation of Hydr...

*UPDATED* For 2022-23 Boards Exam SHOBHIT NIRWAN's DESIGNED CARBON AND ITS COMPOUNDS NOTES  Covalent Bond - Examples of covalent Bonding - formation of Hydrogen molecule - formation of chlorine molecule - formation of Oxygen molecule - formation of Nitrogen molecule - formation of Methane - formation of sulphur properties of covalent Bond Allotropes of carbon f- graphite Diamond - - fullerenes Hydrocarbons - saturated → Alkanes - Unsaturated Alkenes→ & Alkynes Carbon and it’s Compounds IUPAC Nomenclature of Hydrocarbons f- Nomenclature rules 1- How to draw structure functional Groups series Homologous structural Isomerism some compounds Important carbon - Ethanol - Ethan oic acid.  Atomic number of carbon 6 { & - Hat at stable tetetgtend - stable configuration :O Its electronic att I hit 85041¥ etat (in , → outermost shell) but UET 4k¥ Ha at tf - 274 that 21T 4 lose the II gain gain four electrons forming Ct anion , but it would be difficult for the - ° It could olnyfkahfdtfosheoldougixefechrtoonnstfoohmoihdg.nu of energy to #catenane' Tutto't would , ' require a large amount f remove four electrons.. ⑧based hfgt.ge#afaf*tagilEH5Tl9hThFeHGuyzz9i , But of stat carbon 20M Therefore in order to , this problem, overcome carbon shares its valence electrons with other atoms of carbon or with atoms of other elements These shared electrons. to the belong outermost shells of both atoms and in this way , both atoms attain the nearest noble gas configuration This type of bonding is called. covalent Bonding. EXAMPLES OF COVALENT BONDING IN formation of Hydrogen Molecule ( Hz) : Hg Atomic no. =L ' I Electronic configuration = -0 to Need I more e till K shell - completely ooo two H atoms. - share their electrons gas configuration to form a Hz molecule , also it will attain nearest noble ie of helium. H* t * H - H ¥ H or t.ee H. T covalent bond III Formation of chlorine Molecule (Ck) : k3B* f single bond ( because aint - -0 Eti th e share D Cdg Atomic no = 17 single bond E b II. - = Electronic configuration g I. I no Need 1 more e -0 in outermost shell to complete octet. :c :*. + ¥¥¥ - ¥:* : i:* or eerie single covalent bond. III formation of Molecule CO2 ) Oxygen or 0g Atomic number 8 I I - - Electronic configuration = , Need 2 more e -0 to complete octet 4 attain Noble gas. configuration. ¥: : + : :O: - :O:* : : oooo -0 2e share → singlebond G-d Yeo share → double bond :(2.9 similarly it 60 share ? ↳ triple bond t.EE) INI formation of Nitrogen Molecule ( Nz ) : - Ng Atomic No. = 7 E I Electronic configuration = , Need 3 more eos to complete octet 4 achieve noble gas configuration.. ii. ¥ + *¥ - : n ¥ :*. ii. or NEN N formation of Methane cc Hy) : H. H H * * l H. * ( K. H → H * C *. H → H - C - H * * I H H H k¥3 Methane also called marsh gas g used as a fuel and B a major component of CNG ( compressed Natural Gas) and Biogas. ttf HI GIT compounds IT 3447 3-HT 9.413¥ : - → Ammonia ( N Hs) → Water ( H2O) - carbon Dioxide ( CO2) HIT formation of Sulphur (Ss) : - → # Properties of covalent Bond : ( Cbse 2019 20181 , ° Low melting and boiling points too weak inter molecular forces). in As electrons are shared between atoms and no charged particles are formed ° these compounds. Allotropes of carbon ↳ Allotropy is the property by which an element exists in more than one form and each form has different physical Properties but identical chemical prop. DIAMOND GRAPHITE Very Hard diamond , Property lighter than slippery - o o ° o Non conductor of - colourless transparent Electricity o 0 conduct Electricity Greyish black , opaque Uses - o Used as a cutting instrument o used as a lubricant ° Making jewellery 0 Used in electric cell ° To make core of pencil. # fullerenes : fullerene ( Coo) was named Buk Minster fullerene The first known. fullerene was Go which contains 60 carbon atoms.  - K' B CARBON IT 21¥ Jal we 42T It ? ⑧ g what are the factors that enables carbon to form large no. of compounds? ⑧ , versatile Nature of carbon : (Cbse 20201 - L. CATENATION carbon has a self linking property in which C- atoms : - links through covalent bonds to form long , straight or bra need chains and rings Carbon shows maximum catenation in the periodic table.. due to its small size and strong C C bond -. 2. TETRA VALENCY OF CARBON : carbon has 4 eos in outermost shell Hence, its. valency is four ie it is capable of bonding or pairing with four other carbon. atoms or with the atoms of some other monovalent elements like hydrogen , halogen ( chlorine , bromine ) etc. 3. TENDENCY FORM MULTIPLE BONDS : Due to its small size carbon has a strong TO tendency to form multiple bonds ( double and triple bonds) by sharing more than pair with its own atoms or with the atoms like oxygen , nitrogen etc -0 one. ⑧ Compounds of carbon are called Organic compounds. Hydrocarbons. lcbse 2017.20121 A compound made of hydrogen and carbon only is called hydrocarbon. Types of Hydrocarbons - I. SATURATED : compounds of carbon which are linked only by single bonds between the carbon atoms. Types of saturated hydrocarbons - Alkanes. 2. UNSATURATED : Compounds of carbon having carbon atoms double or triple bonds between their. Types of Unsatured hydrocarbons - Alkenes g Alkynes. ¥10 WAYKanes : The hydrocarbons in which all the carbon atoms are linked by only single covalent bonds are called alkanes or paraffin s. General formula Cn Hzntz Alkenes : Those unsaturated hydrocarbons which have at least one double bond along with single bonds are called alkenes. or Olefins. General formula Cn Hzn In > 4 Alkynes : Those unsaturated hydrocarbons which have one or more triple bonds  along with the single bonds are called alkynes. *. General formula : Cntkn - z In > IT here In Dire > minimum no. of carbon for double triple or bond must be two. = ↳ HAT carbon at doublet triple bond et that insist ! IUPAC Nomenclature of Hydrocarbons HIATT ) ↳ 4141907 AT IT lit : - PREFIX + SUFFIX - left aettittl If → Prefix is based on number of carbon atoms in the chain. Prefix Cs → Meth Cz → Eth # Rata MaarLo : - Cz → Poop Cy → But Cs → pent CG → Hex → Suffix is based on it hydrocarbon is alkane , alkene g alkyne. Suffix Alkane - ane # Rata Maar lo : Alkene → ene Alkyne → yne Method : o suffix I total no of carbon at lifted DWI 31K¥ at. ° THAT hydrocarbon E 2741T him if ro of Gte compound ight fat tidal formulae tf Att It (like Cn In iz g Cn Heng Cn Han 2) - - " " : Cz Hy carbon 2 :O Eth is prefix elf → - alkene " in Cn Han we " If we put A- 2 get catty - so its → To ene is suffix. % Name → Prefix -1 Suffix - Ethene '' G- Hu prefix i' Pent fs Pentane - suffix → " ane " f : put n -5in - Cn Hantz to get G- His ) - tf Ctb CHIH , - Get club up - th simplify that ) i = CzH8 Prefix " ↳ Now " , Affix → → " prop ane " Is propane - " " Cz Hy Prefix prop t Propylene - → " " suffix → yne  → fc bye 20151 # HOW TO DRAW STRUCTURE OF SATURATED AND UNSATURATED COMPOUNDS: CB connect all the carbon atoms together with single bond. EB After that use the hydrogen atoms to satisfy the remaining valencies of carbon (as we know, carbon forms 4 bonds due to its 4 valency). Iii) It number of available H atoms are less than what is required , satisfy - remaining valency by using double or triple bond. ↳ Trick → → yet et ITT at # Alkane , alkene at Alkyne Ehs formulae tf I at IBT Helf et Ite htt etat tf double gtriple AT MYATT Bond 41¥ = I et Rs Cz H 8 Name Propane → all single bonds HIT steps follow tht +, +, Is. To simple 34T l l l H - C - C - C - H l l l H H H Eu, ez Hy Ethenes → , double bond H H H - c' =D - H ai, Cz Hy → PROPHET le boyd. Triple bond 91¥ tf tf That sit the DHT at# ofgiant H - C E C - C I 1 - H ← f Triple bond IF carbon ¥ HTT Hydrogen 44114 GT TH HIT WHIT 4244T 4 tf salat Bond AT IT TITI ] H t Ev, cyclohexane ( GHz) " FT ¥3 enzene Cca Hs) ( Ratt do) (Cbse 2018 ) M \ IH H H ' C GH ' d * d c H - H Y - H l - ' l C H H ll l tf ' H C - H C H E - - Functional Groups l H. L atom that makes An atom or group of a carbon compound reactive and decides its chemical bro Peaty is called a functional group. fcbse 20161. M fornicator : functional is present in the compound It group it is - , indicated in the name of the compound with either prefix a or suffix (given on next page)  Pretty suffix f- Prefix - Chloro , Bromo - - - loose zones Tutti's: oaf : suffix - one suffix - Oic acid o : for nomenclature do → Prefix Hydrocarbon+ org Hydrocarbon + Suffix ' final and add the ' In suffix case , delete the e appropriate suffix. → egg CHZCL or H - ¥ , - Ce → Prefix + Hydrocarbon Chloroethane ft ft Hydrocarbon suffix ( but delete e ) ' ' CHSCHZOH or H - - - OH → + Ethane # Ethanol , - e H CHZCHO or H - ¥ - E- O → Hydrocarbon + suffix H Ethane ¥ Ethanol CHS COCH , or H - ¥ -8¥ , H - H Propane tones Propanone O C Hz COOH or H - - E - OH Ethane ±ds Ethan ope e acid - Homologous series ( cbse 2017,20133 ↳ A is similar structure homologous series having group of organic compounds differ a and chemical property in which successive compound group by - CH, group. (Hy GHG GHS eg : - - g - g - - characteristics : o All members are represented by same General formula ° 2 adjacent members differ by Ctb - group. o -2 members adjacent differ by Mol masses of Hu.. ° All shows similar chemical properties. ( but not physical)  STRUCTURAL ISOMERISM ↳ compounds with identical molecular formula but different structures '¥÷÷¥÷÷ ti ¥ f 's:# ¥ :: sunt :*:*:its " * a. e. Igo mess. Some Important carbon compounds Ethanol ( C Hz CHZOH) : ° Liquid soluble in water , ° Commonly it is a called alcohol and is active ingredient solvent , it is used in medicines such as tincture iodine, As good ° cough syrups and many tonics. ° Preparation obtained - fermentation of molasses which are obtained by from sugarcane juice III C-than Oic Acid kHz COOH) : ° Commonly called acetic acid. ° 5- 8% solution of acetic acid in water is called vinegar which is used as presentation in pickle. 290k , so freezes during winter ° Melting point. 0 Carboxylic acid are weak acids. some Important call u Problems : Cbscad ans → = ⑧④ frozen acetic acid Cats OH) is also called glacial acetic acid. ° DENATURED ALCOHOL : consumption of Alcohol in large quantity is not good for health It tends to slow metabolic. processes and depress the central nervous system which in turn results in lack of coordination drowsiness etc Therefore gin order ,.. to stop misuse of alcohol, it is made unfit for drinking by adding poisonous substances like methanol , pyridine etc and coloured substances likes dyes Such alcohol is. called denatured alcohol. KHAI AM  —- Chemical Properties of Carbon Compounds —- 1. COMBUSTION: A chemical reaction in which heat and light are given out is called combustion. - Combustion of Carbon: C(s) + O2(g) CO2(g) + Heat + Light - Combustion of Hydrocarbon: CH4(g) + O2(g) CO2(g) + H20(g) + Heat + Light - Combustion of Alcohol: CH3CH2OH (g) + O2(g) CO2(g) + H20(g) + Heat + Light The Nature of Flame: Saturated hydrocarbon such as, methane, ethane burn with clear b/w flame in the presence of su cient oxygen. Saturated hydrocarbon in the presence of Limited amount of oxygen give sooty Flame Unsaturated hydrocarbon such as ethene, ethyne etc. burn with yellow flame with lots of black smoke Kerosene when burnt in the presence of su cient oxygen gives clear between flame. Some hydrocarbons like benzene, naphthalene etc. burn with sooty flame. Coal and Petroleum on burning produce mainly CO2, CO, Oxides of Nitrogen and sulphur. The oxides of Nitrogen and sulphur cause air pollution. 2. OXIDATION: Carbon compounds can be easily oxidised on combustion. 2C(s) + O2(g) —-> 2CO(g) Limited Carbon Monoxide C(s) + O2(g) —-> CO2(g) Excess Carbon Monoxide *Di erent amount of oxygen gives di erent products. Oxidation of Alcohol: (CBSE 2020) *Both Alkaline KMnO4 and acidified K2Cr2O7 act as oxidising Agents (substance that supplyoxygen for oxidation) 3. ADDITION REACTION:  Unsaturated hydrocarbon add hydrogen in the presence of catalyst such as palladium or Nickel to give saturated hydrocarbons. *Catalysts are the substances that cause a reaction to occur at a di erent rate, without being used up in the reaction. Hydrogenation Reaction: This reaction is used in the hydrogenation of Vegetable oil Vegetable oil generally have long unsaturated carbon chains while animal fats have saturated carbon chain. Animal fats generally contain saturated fatly acid which are harmful for health. 4. SUBSTITUTION REACTION: It is a single replacement chemical reaction during which one functional group in chemical compounds is replaced by another functional groups. CH3OH + HBr —-> CH3Br + H2O hv CH4 + Cl2 —-> CH3Cl + HCl 5. Reactions of Ethanol: i. Reaction with sodium: 2Na + 2CH3CH2OH —-> 2CH3CH2O-Na+ + H2 (sodium ethoxide) ii. Reaction to give unsaturated hydrocarbons: Hot conc. CH3-CH2-OH ——-> CH2 = CH2 + H20 H2S04 *Hot conc. H2SO4 act as dehydrating Agent(which removes water) 6. Reactions of Ethanoic Acid: i. Esterification Reaction: Reaction of Acid and alcohol girs ester. Esters are sweet smelling substances used in making perfumes and as flavouring agents. ii. Saponification Reaction: Reaction used in preparation of soaps. Ester + base —-> Alcohol + Carboxylic Acid NaOH CH3COOC2H5 —-> C2H5OH + CH3COONa (alcohol) (sodium acetate) NaOH + CH3COOH —-> CH3COONa + H2O  ii. Reaction with Carbonates and Hydrogen Carbonates: 2CH3COOH - Na2CO3 —-> 2CH3COONa + H2O + CO2 CH3COOH + NaHCO3 —-> CH3COONa + H2O + CO2 —- Soaps and Detergents —- Soaps are sodium or potassium salts of long chain carboxylic acids. The ionic - end of soap dissolve in water the carbon chain dissolves in oil. Detergents are generally ammonium or sulphonates salts of long chain carboxylic acid. Cleaning Action of Soap: ○ Most of the dirt is oily in nature and oil does not dissolve in water ○ The soap molecule form the structure called Micelles ○ In Micelles one end is towards the oils droplet and other end which is ionic faces outside. ○ Soap in the form of a micelle in the centre of the micelles ○ The micelles stay in the solution as a colloid and will not come together to precipitate due to ion ion Repulsion. ○ Soap micelles are large enough to scatter light; Hence soap solution appears cloudy. Hardness of Water ○ Hard water means, water having a very high a mineral content like calcium and Magnesium salts soap molecule react with the salts of calcium and magnesium and for precipitate also known as sum. ○ Soft water (which do not contain calcium and Magnesium salts are) do not form sum with soap. ○ Detergents are generally ammonium or sulphonates salts of long chain carboxylic acid. The charged ends of these compounds do not form insoluble precipitates with Hardwater, thus they remain e ective in Hard water. LP: Why detergents are better cleansing agents than soaps? Ans- The charged ends of detergents do not form insoluble precipitates with calcium and magnesium ion in Hard water, while when soaps are used for washing clothes with hardwater, it react with the calcium and magnesium ions of hardwater to form an insoluble precipitate called scum; therefore detergents are better cleansing agents than soaps, because they can be used even with hard water.  -- PREVIOUS YEAR QUESTIONS -- 1 MARK QUESTIONS (INCLUDING MCQs) Q1. What is the difference in the molecular formula of any two consecutive members of a homologous series of organic compounds? [CBSE 2008] A.1 The molecular formula of any two consecutive members of homologous series differ by CH2 units. Q2. Write the molecular formula of the 2nd and 3rd member of the homologous series where the first member is ethyne. [CBSE 2017] A.2 The molecular formula of the 2nd and 3rd members of a homologous series where the first member is ethyne (C2H2) is formed by adding -CH2 -: 2nd member of alkyne series = propyne (C3H4) CH3-CH2-C≡CH 3rd member of alkyne series = butyne (C4H6) CH3-CH2-C≡CH Q3. Write the name and formula of the 2nd member of the series of carbon compounds whose general formula is CnH2n. [CBSE 2012] A.3 C3H6------> Formula H2C=CH-CH3------> Structure Propene is the second member of the series whose general formula is CnH2n. Q4. Write the molecular formula of the 2nd and the 3rd member of the homologous series whose first member is methane. [CBSE 2017] A.4 2nd member - Ethane C2H6 3rd member - Propane C3H8 Q5. Which element exhibits the property of catenation to maximum extent and why? [CBSE 2016] A.5 Carbon exhibits the property of catenation due to it's strong C-C bond. Q6. Draw the electron dot structure of Nitrogen molecule. [CBSE 2012,2013] A.6 This is the electron dot structure of nitrogen molecule. 7. Ethane, with the molecular formula C2H has a). 6 covalent bonds b). 7 covalent bonds c). 8 covalent bonds d). 9 covalent bonds A.7 b). 7 covalent bonds 3 MARKS QUESTIONS Q8. State the reason why carbon can neither form C4+ cations nor C4- anions but forms covalent compounds. Also, state reasons to explain why covalent compounds: (i) are bad conductors of electricity? (ii) have low melting and boiling points? [CBSE Compt. 2017, CBSE 2019] A.8 The atomic number of Carbon is 6 with an electronic configuration of 2, 4. Hence, carbon has 4 electrons in its valence shell. Carbon can lose or gain 4 electrons in order to gain stability. It cannot gain four electrons as carbon atom having 6 protons is very small to handle 10 electrons and it cannot donate electrons as it needs a lot of energy to do so. Hence, it cannot form C4+ anion or C4- anion and thus forms a covalent bond. 1. Covalent compounds are formed by sharing of electrons. They don't have a free electron that is required for electricity transfer (electricity is the flow of free electrons), thus they are bad conductors. 2. Covalent compounds have low melting and boiling points because they have weak intermolecular forces between bonds. Hence, less energy/temperature is needed to break the bonds. Q9. Give reasons for the following: (i) Element carbon forms compounds mainly by covalent bonding. (ii) Diamond has a high melting point. (ii) Graphite is a good conductor of electricity. [CBSE 2011] A.9 (i) It is because carbon has four valence electrons, it cannot gain or lose four electrons because high energy is needed. It can only share four electrons. (ii) It is due to strong covalent bonds and compact structure of diamond. (iii) It is due to presence of free electrons in graphite because each carbon is linked to three more carbon atoms. Q10. Carbon a member of group 14, forms a large number of carbon compounds estimated to be about three million. Why is this property not exhibited by other elements of this group? [CBSE 2020] A.10 This property of carbon is known as catenation which is exhibited only carbon atom not by other elements of this group. Due to the small size of carbon atoms , stability of carbon atoms and ability to form strong bonds , carbon gives rise to a large number of compounds linked to each other. Q11. (a) Why are most carbon compounds poor conductors of electricity? (b)Write the name and structure of a saturated compound in which the carbon atoms are arranged in a ring. Give the number of single bonds present in this compound. [CBSE 2018] A.11 a) Electricity is conducted by moving electrons. But carbon forms covalent bonds by sharing electrons. Hence, it does not have free electrons. (b) Cyclohexane is a saturated compound in which carbon atoms are arranged in a ring. 6 single bonds present in this compound. 5 MARKS QUESTIONS Q12. (a) Explain why carbon forms covalent bond? Give two reasons for carbon forming large number of compounds. (b) Explain the formation of ammonia molecules. A.12 (a). The atomic number of Carbon is 6 with an electronic configuration of 2, 4. Hence, carbon has 4 electrons in its valence shell. Carbon can lose or gain 4 electrons in order to gain stability. It cannot gain four electrons as a carbon atom having 6 protons is very small to handle 10 electrons and it cannot donate electrons as it needs a lot of energy to do so. Hence, it cannot form C4+ anion or C4- anion and thus forms a covalent bond. (b). Ammonia (NH3) is made up of one atom of nitrogen and three atoms of hydrogen Atomic number of N = 7 Electronic configuration = 2, 5 Atomic number of H = 1 Electronic configuration = 1 So hydrogen needs more electron to complete its duplet and nitrogen needs three more electrons to complete its octet. Hence three hydrogen atoms will combine with nitrogen to form ammonia. ASSERTION AND REASONING QUESTIONS Rule : Assertion is labelled as (A) and the Reason is labelled as (R). Select the correct answer to these questions from the codes (a), (b), (c) and (d) as given below : (a) Both (A) and (R) are true and (R) is the correct explanation of the assertion (A). (b) Both (A) and (R) are true, but (R) is not the correct explanation of the assertion (A). (c) (A) is true, but (R) is false. (d) (A) is false, but (R) is true Q13. Assertion: Carbon has ability to form long carbon chains. Reason : Carbon has unique property of ability to chain and branched chains called catenation. A.13 (a) Both assertion (A) and reason (R) are correct and reason is the correct explanation of assertion. Q14. Assertion: Second number of alkane is ethane (C2H6). Reason : It is obtained from general formula CnH2n+2. A.14 (a) Both assertion (A) and reason (R) are correct and reason is the correct explanation of assertion.