Organic Chemistry Student 1 PDF

Organic Chemistry Wendy Kendy T. Lannaon Terms To Know Hydrocarbon Alkane Alkene Alkyne Saturated Unsaturated Petrochemicals Functional Groups Polymers Isomers Skills To Master Differentiating alkanes, alkenes, and alkynes Differentiating saturated an...

Organic Chemistry Wendy Kendy T. Lannaon Terms To Know Hydrocarbon Alkane Alkene Alkyne Saturated Unsaturated Petrochemicals Functional Groups Polymers Isomers Skills To Master Differentiating alkanes, alkenes, and alkynes Differentiating saturated and unsaturated compounds 1. Cyclic organic compounds possessing the properties of aliphatic compounds are called ___ compounds. a. Aromatic c. Carbocyclic b. Homocyclic d. Alicyclic 2. The formula which represents the simple whole number ratio of different atoms present in one molecule of a compound is known as : a. Molecular formula c. Condensed formula b. Empirical formula d. Electron dot formula 3. An organic compound has empirical formula CH2O and molecular weight 90. It’s molecular formula will be : a. C6H12O6 c. C2H4O2 b. C3H6O3 d. C3H9O6 4. General formula of an alkene is : a. CnH2n c. CnH2n-2 b. CnH2n+2 d. CnH2n-1 5. A hydrocarbon is found to contain 81.80% carbon and 18.20% hydrogen. It’s empirical formula will be: a. C4H8 c. C3H8 b. C2H6 d. C3H 6. If two compounds have same empirical formula but different molecular formula, they must have : a. Different percentage composition b. Different molecular weight c. Same viscosity d. Same vapour density 7. Which of the following is an aromatic compound : a. Benzene hexachloride c. Cyclobutane b. Cyclohexane d. Toluene 8. Which of the following is a heterocyclic aromatic compound : a. Nephthalene c. Furan b. Benzene hexachloride d. Toluene 9. Which of the following belongs to a homologous series ? a. Methanol, Ethanol, ethanoic acid b. Propane, Propene, propyne c. Butane, 2-methylpropane, 2-methylbutane d. Chloroathane, 2-chloropropane, 1- chlorobutane 10. Which of the following is not true about homologous series ? a. Adjacent members of group differ by one –CH2 group. b. Adjacent members of group differs by a mass of 14 amu. c. Members of a group have same chemical and physical properties. d. Members of a group can be prepared by same general methods. a. Isomers c. allotropes b. Homologues d. None 12. Alkanes are also called: a. Paraffins c. Acetylene b. Olefins d. Both ‘a’ and ‘b’ A. What is Organic Chemistry? Organic chemistry is the study of carbon compounds Organic compounds have carbon AND hydrogen Carbon Dioxide is NOT organic over 16 million carbon-containing compounds are known because the C-C single bond (348 kJ mol-1) and the C-H bond (412 kJ mol-1) are strong, carbon compounds are stable versatility and stability of carbon’s molecular structures provides the enormous range of properties of its compounds carbon can bond to other carbons reason for the degree of structural complexity carbon can form chains and rings Organic Chemistry… Carbon Has 4 valence electrons Makes 4 covalent bonds to fill its octet Can include double and triple bonds Hydrocarbon Compound with only carbon and hydrogen  B. Organic Chemistry in Everyday Life Smells & tastes: fruits, fish, mint Medications: aspirin, Tylenol, decongestants, sedatives, insulin Addictive substances: caffeine, nicotine, alcohol, narcotics Hormones/Neurotransmitters: adrenaline, dopamine, serotonin Food: carbohydrates, protein, fat, vitamins Genetics: DNA, RNA Consumer products: plastics, nylon, rayon, polyester  Methane (CH4): A most Basic organic compound. Ethanol (C2H5OH): A colourless liquid alcohol used as a solvent, and fuel, and also used in alcoholic beverages. Glucose (C6H12O6): A simple sugar that is an essential energy source for living organisms. Amino Acids: Amino acids are building blocks of life which form all the proteins necessary for life to exist. Chlorophyll (C55H72O5N4Mg): Green pigment in plants which gives plants their green colour and help them make food as well. Vitamin C (C6H8O6): Vitamin C is a water-soluble vitamin which is essential for the growth and repair of the human body. DNA (Deoxyribonucleic Acid): A complex organic molecule which stores the instruction for life. Polymers: Large molecules made with repeating subunits known as monomers. Some examples include polyethene and polystyrene. Organic Materials Addition to previous notes Before, it was stated that covalent compounds were mostly liquid/gas at room temp This is primarily for binary compounds (2 elements) More complicated structures can be solid at room temperature  C. Classification of organic compounds (Hydrocarbons) organic compounds are defined as the hydrocarbons (compounds containing carbon and hydrogen) and their derivatives in which covalently bonded carbon is an essential constituent  General Formulas Alkanes Contains only single bonds Cx H2x+2 Alkenes Contains at least one double bond Alkynes Contains at least one triple bond Alkenes and Alkynes are more reactive than alkanes  Saturation Saturated: a carbon chain contains as many hydrogen as possible. Saturated compounds contain only single C-H bonds. Alkanes are saturated. Unsaturated means that a carbon chain contains at least one multiple (double or triple) bond. – Alkene = double bond – Alkyne = triple bond  Hydrocarbons IUPAC Molecular Structural Boiling name Formula Formula Point (°C). Methane CH4 CH4 -161.5 Ethane C2H6 CH3CH3 -88.6 Propane C3H8 CH3CH2CH3 -42.1 Butane C4H10 CH3(CH2)2CH3 -0.5 Pentane C5H12 CH3(CH2)3CH3 36.1 Hexane C6H14 CH3(CH2)4CH3 68.7 Heptane C7H16 CH3(CH2)5CH3 98.4 Octane C8H18 CH3(CH2)6CH3 125.7 Nonane C9H20 CH3(CH2)7CH3 150.8 Decane C10H22 CH3(CH2)8CH3 174.1 1. Open chain organic compounds Organic compounds in which the terminal C-atoms are not joined together are called open chain compounds Examples: 1.1. Alkanes saturated hydrocarbons with general formula CnH2n+2 contain only carbon-carbon and carbon-hydrogen single bonds in their molecules also called paraffins (because they have a little affinity towards a general reagent. In other words, alkanes are less reactive substances. They undergo reactions under drastic conditions) Alkanes are called saturated because all the possible sites (i.e. 4) are bonded with other atoms. But in alkenes and alkynes there is a possibility of addition of atoms or groups so they are called unsaturated. Some examples: Methane - Natural gas Ethane - Also natural gas Propane - outdoor grills/home heating Butane - lighters Pentane, Hexane, Heptane, Octane, Nonane, Decane - all found in gasoline Candle wax - 20 or more carbon atoms Road Tar - 40 or more carbon atoms 1.2. Alkenes unsaturated hydrocarbons with general formula CnH2n they contain at least one carbon to carbon double bond in their molecules Examples: also called olefins ( i.e. oil forming because they form oily liquids on reaction with chlorine gas) 1.3. Alkynes unsaturated hydrocarbons with general formula CnH2n-2 they contain at least one carbon to carbon triple bond in their molecules Examples: 2. Closed chain/cyclic compounds Organic compounds in which the terminal carbons are joined together to form a cyclic structure 2.1. Homocyclic compounds the ring forming atoms are only carbon specifically called carbocyclic compounds 2.1.a. Alicyclic compounds closed chain organic compounds whose properties are similar to open chain aliphatic compounds Examples: 2.1.b. Aromatic compounds benzene and those cyclic compounds that chemically behave as benzene Examples: they obey Huckel’s rule Huckel’s rule states that a cyclic and planar molecule is aromatic if it contains 4n+2 delocalized π electrons, where n = 0,1,2,3,4,etc. Example: benzene HOW? : https://youtu.be/wvJ5V5cghOM 2.2. Heterocyclic compounds at least one heteroatom (i.e. atom other than carbon eg. N, O or S ) is present as one of the ring forming atoms Examples : D. Formula of Organic Compounds 1. Molecular formula 2. Empirical formula 3. Electron-dot formula 4. Structural formula 5. Contracted or condensed formula 6. Bond-line formula 7. Spatial formula  it represents actual number of atoms of all the elements present in one molecule of the compound 1. Molecular Examples: formula methane = CH4 ethane = C2H6 ethene = C2H4 benzene = C6H6 , etc.  it represents simple whole number ratio of atoms of all the elements in one molecule of the compound 2. Empirical Examples: formula ethane = CH3 ethene = CH2 benzene = CH , etc  in this formula valence electrons are represented by dots placed around the chemical symbol 3. Electron- it is also called Lewis dot formula dot formula Examples:  it indicates how the atoms are bonded in a molecule of the compound a.k.a. Kekule structural 4. Structural formula formula Examples:  it is the structural formula in contracted form to save space and time 5. Contracted Examples: or condensed formula  carbon and hydrogen atoms 6. Bond-line are not shown and only hetero atoms are shown formula the point of intersection represents carbon along with required number of hydrogen to satisfy the valency of carbon  this formula represents the 7. Spatial three dimensional shape or arrangement of atoms in the formula molecule Examples: E. Functional Group an atom or group of atoms in a molecule which largely determines the chemical properties of the organic compounds is known as functional group all the compounds having same functional group show similar properties and constitute a class or a family  Example: Alcohol having an –OH as functional group  Other examples of functional group  Homologous Series/Compounds the series of organic compounds having same general formula and similar chemical properties but different physical properties in which one member differs from other member by single – CH2 unit Examples: each member of homologous series is called homologue and phenomenon of making homologous series is called homolog  Characteristics of homologous series: a. All the members of homologous series have same functional group b. All the members of homologous series have same chemical properties c. All the members of homologous series can be prepared by a common method of preparation d. All the members of homologous series can be represented by same general formula CnH2n+2 = Alkane CnH2n = Alkene CnH2n-2 = Alkyne CnH2n+1OH = Alcohol, etc e. Their molecular masses increases gradually hence their physical properties (e.g. melting point and boiling point) changes gradually - physical properties vary in regular manner as the number of C atoms increases  Structure and Physical Properties Methane Ethane Propane Butane 16 g/mol 30 g/mol 44 g/mol 58 g/mol -161.5oC -88.6oC -42.1oC -0.5oC Larger molar mass = higher boiling point Bigger compound – higher boiling point f. Each member differs from the adjacent member by methylene (-CH2-) unit  Trends in boiling points of members of a homologous series melting point and Alkane Formula Boiling boiling point increase Pt./oC with more carbon atoms methane CH4 -162.0 Why? intermolecular forces increase adding a CH2 adds ethane C2H6 -88.6 more electrons this increases the Van propane C3H8 -42.2 der Waal’s forces butane C4H10 -0.5  Petrochemicals Simple, small hydrocarbons are petrochemicals Chemicals isolated from crude oil (petroleum) Octane – used in gasoline Propane – used in grills, heaters, etc. Butane – lighter fluid  Polymers Large molecules with many, many repeating units, made from smaller molecules CH2 CH2 n Polyethylene Polymer ex… Nylon, Kevlar, and PVC are other examples of manmade polymers Nylon PVC (polyvinyl chloride) Natural polymers examples… Proteins RNA Natural Polymer… Polysaccharides DNA Pharmaceutical examples Most pharmaceuticals are complex, organic molecules Can be natural or manmade aspirin penicillin Acetaminophen (aka Tylenol)  Isomers (structural) isomers: compounds with the same molecular formula but different structure (arrangement of atoms)  different isomers are completely different compounds have different physical properties such as melting point and boiling point  Structural Formulas for C4H10O Isomers 1. Cyclic organic compounds possessing the properties of aliphatic compounds are called ___ compounds. a. Aromatic c. Carbocyclic b. Homocyclic d. Alicyclic 2. The formula which represents the simple whole number ratio of different atoms present in one molecule of a compound is known as : a. Molecular formula c. Condensed formula b. Empirical formula d. Electron dot formula 3. An organic compound has empirical formula CH2O and molecular weight 90. It’s molecular formula will be : a. C6H12O6 c. C2H4O2 b. C3H6O3 d. C3H9O6 4. General formula of an alkene is : a. CnH2n c. CnH2n-2 b. CnH2n+2 d. CnH2n-1 5. A hydrocarbon is found to contain 81.80% carbon and 18.20% hydrogen. It’s empirical formula will be: a. C4H8 c. C3H8 b. C2H6 d. C3H 6. If two compounds have same empirical formula but different molecular formula, they must have : a. Different percentage composition b. Different molecular weight c. Same viscosity d. Same vapour density 7. Which of the following is an aromatic compound : a. Benzene hexachloride c. Cyclobutane b. Cyclohexane d. Toluene 8. Which of the following is a heterocyclic aromatic compound : a. Nephthalene c. Furan b. Benzene hexachloride d. Toluene 9. Which of the following belongs to a homologous series ? a. Methanol, Ethanol, ethanoic acid b. Propane, Propene, propyne c. Butane, 2-methylpropane, 2-methylbutane d. Chloroathane, 2-chloropropane, 1- chlorobutane 10. Which of the following is not true about homologous series ? a. Adjacent members of group differ by one –CH2 group. b. Adjacent members of group differs by a mass of 14 amu. c. Members of a group have same chemical and physical properties. d. Members of a group can be prepared by same general methods. a. Isomers c. allotropes b. Homologues d. None 12. Alkanes are also called: a. Paraffins c. Acetylene b. Olefins d. Both ‘a’ and ‘b’