Curriculum
Chemistry
Chapter 1 - Transition Elements and Iron Metallurgy
0/28
1.1Where they are in the periodic table1.2The main transition elements (d-block)1.3The four transition series1.4Economic importance of the first-series elements1.5Electron configurations of the first series1.6Rules for filling1.7Configurations of the common ions1.8Why Fe(II) is easily oxidized to Fe(III) but Mn(II) is not1.9Oxidation-state rules for the series1.10Calculating oxidation states in compounds1.11Definition of a transition element
Chapter 2 - Chemical Analysis
0/221.1Revision of concepts and laws needed in this chapter1.2Importance1.3Kinds of analysis1.4Qualitative analysis1.5A. Identification of acid radicals (anions)1.6(1) Dilute hydrochloric acid group1.7(2) Concentrated sulphuric acid group1.8(3) Barium chloride group1.9Practical differentiation between pairs of salts (typical exam type)1.10Reasoning questions1.11Detailed Comparison Matrix: Diagnostic Silver Nitrate (AgNO3) Confirmatory Matrix
Chapter 3 - Chemical Equilibrium
0/221.1The equilibrium system1.2Types of chemical reactions1.3Chemical equilibrium1.4Rate of reaction1.5Factors affecting the rate of a reaction1.6Nature of the reactants1.7Concentration and the law of mass action1.8Temperature — collision theory1.9Pressure1.10Le Chatelier's principle1.11Catalysts1.12Light
2.1Strong and weak electrolytes2.2Hydronium ion2.3Definitions2.4Ostwald's dilution law2.5Hydronium ion concentration of a weak acid2.6Hydroxide ion concentration of a weak base2.7Ionization of water and the ionic product Kw2.8pH and pOH2.9Solubility and solubility product2.10Summary of key relations
Chapter 4 - Electrochemistry
0/331.1The starting experiment: zinc in copper sulphate1.2The idea behind the galvanic cell1.3Construction of the Daniell cell1.4What happens at each electrode1.5When does the current stop?1.6The salt bridge — what it is and why it is needed1.7Why we need a reference1.8The standard hydrogen electrode1.9Standard electrode potentials1.10Measuring an electrode potential (idea of the experiment)1.11Definition1.12What the series tells us (the conclusions to know)1.13Calculating the cell emf1.14Cell notation (cell diagram)
3.1The electrolytic cell3.2Example: electrolysis of copper(II) chloride solution3.3First law3.4Second law3.5The faraday3.6The working formula3.7Worked examples3.8Electroplating3.9Extraction of aluminium3.10Electrorefining of copper3.11Galvanic cells versus electrolytic cells3.12Scientists and the value of electrochemistry
Chapter 5 - Organic Chemistry
0/721.1Historical background1.2Modern definition1.3Why are there so many organic compounds?1.4Comparison: organic and inorganic compounds1.5Molecular formula1.6Structural formula1.7Isomerism1.8Detecting carbon and hydrogen in an organic compound1.9Classification of hydrocarbons1.10Structure and the homologous series1.11Alkyl radicals (R–)1.12IUPAC nomenclature of alkanes1.13Methane — occurrence and preparation1.14Physical properties1.15Chemical properties of alkanes
5.1Functional groups5.2Alcohols and phenols — the difference5.3Nomenclature of alcohols5.4Classification of alcohols5.5Ethanol — preparation5.6Denatured (methylated) alcohol — "red spirit"5.7Physical properties5.8Chemical properties of ethanol5.9Uses of alcohols5.10Phenols5.11Preparation5.12Physical properties5.13Chemical properties5.14Tests for phenol
6.1The carboxyl group6.2Types6.3Nomenclature6.4Preparation of acetic acid6.5Physical properties6.6Chemical properties6.7Aromatic acids: benzoic acid6.8Important acids and their uses6.9Definition and formation6.10Nomenclature6.11Preparation6.12Physical properties6.13Chemical properties6.14Applications of esters6.15Aspirin6.16Types of organic reactions (summary)6.17Revision key points for Part B
7.1The birth of organic chemistry and the vital-force theory7.2Why organic compounds are so abundant7.3Organic versus inorganic compounds7.4Molecular formula, structural formula and isomers7.5Detecting carbon and hydrogen in an organic compound7.6Hydrocarbons and the alkane series7.7The alkyl radical and IUPAC naming7.8Methane, physical and chemical properties of alkanes7.9Practice with answers7.10Ministry exam traps
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Text lesson
Lesson 5: Hydrocarbon Derivatives – Alcohols and Phenols
Lesson 5: Hydrocarbon Derivatives – Alcohols and Phenols
Overview
Overview
🌳 Concept tree
Lesson 5→Hydrocarbon Derivatives – Alcohols and Phenols
├── Functional groups
├── Alcohols and phenols — the difference
├── Nomenclature of alcohols
├── Classification of alcohols
├── Ethanol — preparation
- ├── Denatured (methylated) alcohol — "red spirit"
├── Physical properties
├── Chemical properties of ethanol
├── Uses of alcohols
├── Phenols
├── Preparation
├── Physical properties
├── Chemical properties
└── Tests for phenol
Lesson 5: Hydrocarbon Derivatives – Alcohols and Phenols · 1 / 16
Functional groups
Functional groups
- In the past organic compounds were grouped by physical properties such as smell and taste, or by a few chemical properties.
- With the progress of chemical analysis it became clear that the properties of a compound are controlled mainly by a particular group of atoms in its molecule, the functional group.
- Functional group an atom or group of atoms, joined in a particular way, that forms part of the molecule and decides the characteristic chemical properties of the whole molecule.
| Class | General formula | Functional group | Example |
|---|---|---|---|
| Alcohols | R–OH | hydroxyl –OH | methanol CH₃OH |
| Phenols | Ar–OH | hydroxyl –OH on a benzene ring | phenol C₆H₅OH |
| Ethers | R–O–R | ether –O– | dimethyl ether CH₃OCH₃ |
| Aldehydes | R–CHO | aldehyde –CHO | ethanal CH₃CHO |
| Ketones | R–CO–R | carbonyl C=O | propanone (acetone) CH₃COCH₃ |
| Carboxylic acids | R–COOH | carboxyl –COOH | ethanoic acid CH₃COOH |
| Esters | R–COO–R | ester –COO– | ethyl ethanoate CH₃COOC₂H₅ |
| Amines | R–NH₂ | amino –NH₂ | ethylamine C₂H₅NH₂ |
- Compounds with the same functional group belong to one homologous series and react similarly.
Lesson 5: Hydrocarbon Derivatives – Alcohols and Phenols · 2 / 16
Alcohols and phenols — the difference
Alcohols and phenols — the difference
- Both contain one or more hydroxyl (–OH) groups.
- If the –OH is attached to an alkyl group (R–) the compound is an alcohol; if it is attached directly to a carbon of a benzene ring (aryl group, Ar–) it is a phenol.
- Both may be viewed as alkyl/aryl derivatives of water (one H of H₂O replaced by R or Ar) or as hydroxyl derivatives of hydrocarbons.
Lesson 5: Hydrocarbon Derivatives – Alcohols and Phenols · 3 / 16
Nomenclature of alcohols
Nomenclature of alcohols
| Comparison aspect | Main idea | Keywords |
|---|---|---|
| Common system |
| wordalcoholaddedafter |
| • | The prefix iso is used when the chain ends in a carbon bearing two methyl groups and one hydrogen: isopropyl alcohol (CH₃)₂CH–OH | prefixusedchainends |
| IUPAC system |
| takelongestchaincontaining |
| Comparison aspect | Main idea | Example | Keywords |
|---|---|---|---|
| • |
| — | CH₃OHmethanolC₂H₅OHethanol |
| The three alcohol isomers derived from pentane |
| 2-dimethyl-1-propanol) | pentanolothersbranchedchains |
| Other examples |
| — | ₂CHCH₂OHmethylpropanoldimethyl |
Lesson 5: Hydrocarbon Derivatives – Alcohols and Phenols · 4 / 16
Classification of alcohols
Classification of alcohols
- (a) According to the number of –OH groups
| Comparison aspect | Main idea | Keywords |
|---|---|---|
| Monohydric |
| CH₃OHC₂H₅OH |
| Dihydric |
| ethyleneglycolHOCH₂CH₂OHethanediol |
| Trihydric |
| threeglycerolglycerineHOCH₂ |
| Polyhydric | more than three –OH: sorbitol (six –OH groups) | threesorbitolgroups |
| (b) According to the type of carbinol carbon |
| carryingmonohydricalcohols |
| Comparison aspect | Main idea | Example | Keywords |
|---|---|---|---|
| Primary (1°) | carbinol carbon is attached to one other carbon (and two H): R–CH₂OH |
| carbinolcarbonattachedCH₂OH |
| Secondary (2°) | carbinol carbon is attached to two carbons (and one H): R₂CHOH |
| carbinolcarbonattachedcarbons |
| Tertiary (3°) | carbinol carbon is attached to three carbons (no H): R₃C–OH |
| carbinolcarbonattachedthree |
Lesson 5: Hydrocarbon Derivatives – Alcohols and Phenols · 5 / 16
Ethanol — preparation
Ethanol — preparation
- Ethanol
- C₂H₅OH
- is the oldest organic compound prepared in industry
- the ancient Egyptians made it by fermenting sugars and starches thousands of years ago.
- Alcoholic fermentation. About 20 % of the world’s ethanol is made by fermenting starch and sugar materials (sugar cane, sugar beet, maize).
- In Egypt it is made from molasses (the sugar-rich residue of sugar refining, containing sucrose), for instance at the Egyptian Sugar and Distillation Company (Hawamdeya).
- Yeast is added:
- C₁₂H₂₂O₁₁ (sucrose) + H₂O —(invertase enzyme of yeast)→ C₆H₁₂O₆ (glucose) + C₆H₁₂O₆ (fructose)
- C₆H₁₂O₆ —(zymase enzyme)→ 2C₂H₅OH + 2CO₂
The resulting dilute alcohol (about 10–15 %) is concentrated by fractional distillation (about 95–96 % ethanol, a constant-boiling mixture with water). - 2. Catalytic hydration of ethene. The main industrial method in petroleum-producing countries: ethene obtained by cracking petroleum fractions is hydrated with steam in the presence of dilute sulphuric or phosphoric acid:
- CH₂=CH₂ + H₂O —(H₃PO₄ or dil. H₂SO₄, heat, pressure)→ CH₃CH₂OH
- Ethanol is therefore called a petrochemical (made from petroleum).
- Note ethene is the only alkene that gives a primary alcohol by hydration; other alkenes follow Markovnikov’s rule and give secondary or tertiary alcohols:
- CH₃CH=CH₂ + H₂O → CH₃CH(OH)CH₃ (2-propanol, secondary)
- (CH₃)₂C=CH–CH₃ + H₂O → (CH₃)₂C(OH)–CH₂CH₃ (2-methyl-2-butanol, tertiary)
- 3. General method: hydrolysis of alkyl halides. Heating an alkyl halide with aqueous alkali (KOH or NaOH) replaces the halogen with –OH:
- R–X + KOH(aq) → R–OH + KX
- CH₃CH₂Br + KOH → CH₃CH₂OH + KBr (primary alcohol)
- CH₃CHBrCH₃ + KOH → CH₃CH(OH)CH₃ + KBr (secondary)
- (CH₃)₃C–Br + KOH → (CH₃)₃C–OH + KBr (tertiary)
Ease of hydrolysis: R–Cl < R–Br < R–I (the weaker the C–X bond, the easier). So alkyl iodides are hydrolysed most easily.
Which halide for which alcohol? methanol ← CH₃X; 2-butanol ← 2-halobutane; 2-methyl-2-pentanol ← 2-halo-2-methylpentane.
Lesson 5: Hydrocarbon Derivatives – Alcohols and Phenols · 6 / 16
Denatured (methylated) alcohol — "red spirit"
Denatured (methylated) alcohol — "red spirit"
- Pure ethanol (96 %) is highly taxed to discourage its use in alcoholic drinks (harmful to health and society).
- Ethanol for fuel, solvent and industry is made cheaper by adding poisonous or ill-smelling substances that are very hard to remove: methanol (causes blindness and madness), pyridine (foul smell) and a coloured dye.
- This is denatured alcohol (converted alcohol, red spirit; about 85 % ethanol, 5 % methanol, 1 % other additive plus colour/odour, rest water).
- It is unfit and illegal to drink.
Lesson 5: Hydrocarbon Derivatives – Alcohols and Phenols · 7 / 16
Physical properties
Physical properties
- Alcohols are neutral, colourless compounds.
- The first members are light liquids, completely miscible with water; the middle members are oily; the higher ones are waxy solids.
- Compared with alkanes of similar molecular mass, alcohols have high boiling points and (the lower members) high solubility in water.
- Both effects are due to the polar –OH group, which forms hydrogen bonds between alcohol molecules themselves and between alcohol and water molecules.
- Boiling points ethanol 78.5 °C; ethylene glycol 197 °C.
- As the number of –OH groups rises, the number of hydrogen bonds rises, and so do solubility and boiling point.
- (Order of boiling point ethanol < ethylene glycol < glycerol < sorbitol.)
Lesson 5: Hydrocarbon Derivatives – Alcohols and Phenols · 8 / 16
Chemical properties of ethanol
Chemical properties of ethanol
- Four types of reaction are distinguished:
- A. Reactions of the hydrogen of the –OH group
| Comparison aspect | Main idea | Keywords |
|---|---|---|
| Reaction with active metals (Na, K) |
| ethanolneutrallitmusshows |
| Ester formation (with carboxylic acids) |
| alcoholsreactesterswater |
B. Reaction of the –OH group (substitution)
- With halogen acids (HX) the –OH is replaced by X
- e.g. ethanol with concentrated HCl in presence of ZnCl₂ (catalyst):
C₂H₅OH + HCl —(ZnCl₂)→ C₂H₅Cl + H₂O
Conversion back→C₂H₅Cl + KOH(aq) → C₂H₅OH + KCl.
C. Reactions of the carbinol group — oxidation
- Alcohols are oxidised by acidified K₂Cr₂O₇ (orange → green) or KMnO₄ (violet colour disappears).
- The oxidation removes hydrogen from the carbinol carbon, first giving an unstable gem-diol (two –OH on the same carbon) which loses water.
| Comparison aspect | Main idea | Keywords |
|---|---|---|
| Primary alcohol → aldehyde → carboxylic acid |
| stepsCH₃CH₂OHCH₃CHOethanal |
| Secondary alcohol → ketone |
| stepCH₃CHCH₃COCH₃propanone |
| Tertiary alcohol |
| hydrogencarbinolcarbonoxidised |
| • | D. Reaction of the whole molecule — dehydration with conc. H₂SO₄ | Reactionwholemoleculedehydration |
At 180 °C (excess acid)one molecule of water is removed from one molecule of alcohol → alkene: C₂H₅OH → CH₂=CH₂ + H₂O.
At 140 °C (excess alcohol)one water molecule is lost from every two alcohol molecules → ether: 2C₂H₅OH → C₂H₅–O–C₂H₅ (diethyl ether) + H₂O.
Lesson 5: Hydrocarbon Derivatives – Alcohols and Phenols · 9 / 16
Uses of alcohols
Uses of alcohols
| Comparison aspect | Main idea | Example | Keywords |
|---|---|---|---|
| Ethanol |
|
| solventoilsfatsresins |
| Ethylene glycol (dihydric) |
| — | antifreezeradiatorscoldcountries |
| Glycerol (trihydric) |
| — | moisturisercreamscosmeticssoftens |
Lesson 5: Hydrocarbon Derivatives – Alcohols and Phenols · 10 / 16
Phenols
Phenols
| Comparison aspect | Main idea | Keywords |
|---|---|---|
| Phenols |
| hydroxyaromaticcompoundsgroups |
| Phenol (carbolic acid), C₆H₅OH |
| greatindustrialimportancestarting |
Lesson 5: Hydrocarbon Derivatives – Alcohols and Phenols · 11 / 16
Preparation
Preparation
- From coal tar by fractional distillation.
- with sodium hydroxide at high temperature and very high pressure (about 300 atm), giving sodium phenoxide which is acidified:
C₆H₅Cl + 2NaOH (≈ 300 °C, 300 atm) → C₆H₅ONa + NaCl + H₂O
C₆H₅ONa + HCl → C₆H₅OH + NaCl
Lesson 5: Hydrocarbon Derivatives – Alcohols and Phenols · 12 / 16
Physical properties
Physical properties
- A colourless, corrosive (caustic) solid with a characteristic odour, m.p. 43 °C.
- It is sparingly soluble in cold water; solubility rises with temperature and it is completely miscible with water above 65 °C.
Lesson 5: Hydrocarbon Derivatives – Alcohols and Phenols · 13 / 16
Chemical properties
Chemical properties
- 1. Acidity — phenol compared with alcohols. Both react with sodium metal releasing hydrogen:
- 2C₆H₅OH + 2Na → 2C₆H₅ONa + H₂↑ ; 2ROH + 2Na → 2RONa + H₂↑.
- But only phenol reacts with sodium hydroxide solution (alcohols do not): C₆H₅OH + NaOH → C₆H₅ONa + H₂O (sodium phenoxide).
- Hence phenol is called carbolic acid.
- The benzene ring withdraws electrons from the oxygen of the O–H group, which makes the O–H bond more polar, longer and weaker, and so the proton leaves more easily. (Phenol is still a weak acid – weaker than carboxylic acids and even carbonic acid.)
- Reaction with halogen acids. In alcohols the –OH can be replaced by X with HX.
- In phenol the C–O bond is shorter and stronger (the oxygen lone pair interacts with the ring), so the –OH cannot be replaced by halogen acids; phenol does not react with HCl.
- Phenol with concentrated nitric acid in the presence of concentrated sulphuric acid gives 2,4,6-trinitrophenol (picric acid):
- C₆H₅OH + 3HNO₃ —(conc. H₂SO₄)→ C₆H₂(NO₂)₃OH + 3H₂O
- Picric acid is an explosive and is used in treating burns; it stains the skin yellow for several days (until the outer skin layer is renewed).
- In acidic or basic medium phenol reacts with methanal (formaldehyde, HCHO): one molecule of methanal joins two molecules of phenol with loss of water; the units keep joining by condensation polymerisation to form a three-dimensional network polymer, Bakelite. Condensation polymers are formed from two kinds of monomers with elimination of a small molecule such as H₂O. Bakelite is a dark-brown thermosetting plastic (it does not soften again on heating), heat-resistant and a good electrical insulator — used for electrical fittings, switches, handles and ash trays.
Lesson 5: Hydrocarbon Derivatives – Alcohols and Phenols · 14 / 16
Tests for phenol
Tests for phenol
- Few drops of iron(III) chloride solution → a violet colour.
- → a white precipitate (2,4,6-tribromophenol).
- (Ethanol, by contrast, gives no colour with FeCl₃ and no precipitate with bromine water; its detection uses the acidified dichromate test of Lesson 10.)
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Lesson 5: Hydrocarbon Derivatives – Alcohols and Phenols · 15 / 16
Part 16
Part 16
- 📖
🔍 In-Depth Explanations, Deductions & Multi-Book Insights:
Chemistry Thanaweya Amma (2026/2027)
- Lesson 5 – Hydrocarbon Derivatives – Alcohols and Phenols
- Detailed Academic Lesson Overview:
- Alcohols and phenols contain the hydroxyl group (-OH).
- Alcohols are aliphatic derivatives classified as primary (1°), secondary (2°), or tertiary (3°) based on carbinol carbon connectivity.
- Phenols are aromatic derivatives where -OH is bonded directly to the benzene ring.
🌳 Hierarchy Classification & Conceptual Roadmap
Alcohols and Phenols Chemistry
├── 1. Classification of Alcohols
| Comparison aspect | Main idea | Keywords |
|---|---|---|
| │ ├── Monohydric |
| EthanolIsopropanolmethylpropanol |
| │ ├── Dihydric |
| EthyleneglycolTrihydricGlycerol |
| │ └── Industrial Manufacture of Ethanol | Fermentation of Molasses (Sucrose) or Hydration of Ethene | FermentationMolassesSucroseHydration |
| • | ├── 2. Chemical Oxidation of Alcohols (using acidified K2Cr2O7 or KMnO4) | ChemicalOxidationAlcoholsusing |
| │ ├── Primary (1°) | Oxidizes in 2 steps: Alcohol → Aldehyde → Carboxylic acid | OxidizesstepsAlcoholAldehyde |
| │ ├── Secondary (2°) | Oxidizes in 1 step: Alcohol → Ketone | OxidizesstepAlcoholKetone |
| │ └── Tertiary (3°) | Does NOT oxidize under ordinary conditions (no H on carbinol C) | Doesoxidizeunderordinary |
└── 3. Phenols (Carbolic Acid C6H5OH)
| Comparison aspect | Main idea | Keywords |
|---|---|---|
| ├── Acidity of Phenol |
| Stronglyacidicalcoholsbenzene |
| ├── Reactions | Reacts with NaOH to form sodium phenoxide (alcohols DO NOT react with NaOH) | ReactsNaOHformsodium |
| • | └── Diagnostic Tests for Phenol | DiagnosticTestsPhenol |
| • | ├── Addition of FeCl3 solution produces a deep violet coloration | AdditionFeCl3solutionproduces |
| • |
| Additionbrominewaterproduces |
| • | 📋 Master Teacher's Blackboard Rules & Exam Secrets | MasterTeacherBlackboardRules |
| RULE 1 | Tertiary alcohols resist oxidation with acidified dichromate because their carbinol carbon is attached to zero hydrogen atoms | Tertiaryalcoholsresistoxidation |
| RULE 2 |
| Phenolssignificantlyacidicalcohols |
| RULE 3 |
| Diagnostictestsuspecteddrunk |
| 📊 Detailed Comparison Matrix | Comparative Analysis: Aliphatic Alcohols vs. Aromatic Phenols | ComparativeAnalysisAliphaticAlcohols |
| Property / Reaction | Aliphatic Alcohol (e.g., Ethanol) | Aromatic Phenol (Carbolic Acid) |
|---|---|---|
| Reaction with Sodium (Na) | Reacts evolving H2 gas | Reacts evolving H2 gas |
| Reaction with Aqueous NaOH | NO reaction (Weak acidity) | Reacts forming Sodium phenoxide + H2O |
| Reaction with Conc. HCl | Reacts forming alkyl chloride + H2O | NO reaction (C-O bond is extremely strong) |
| Addition of Neutral FeCl3 | No visible change | Produces distinct deep violet coloration |
| Addition of Bromine Water | No visible change | Produces white ppt (2,4,6-tribromophenol) |
Lesson 5: Hydrocarbon Derivatives – Alcohols and Phenols · 16 / 16
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