Grade 11
  1. Basic concepts of chemistry  1.1. Importance of Chemistry  1.2. Nature and scope of chemistry  1.3. laws of chemical combination  1.3.1. Law of conservation of mass  1.3.2. Law of definite proportions  1.3.3. Law of multiple proportions  1.3.4. Law of gaseous volume  1.3.5. Avogadro's Law  1.4. Dalton's atomic theory  1.5. Mole concept and molar mass  1.6. Percent composition  1.7. Empirical and molecular formula  1.8. Stoichiometry and Stoichiometric Calculations  1.9. Limiting reagent concept
  2. Structure of the atom  2.1. Discovery of the electron, proton, and neutron  2.2. Atomic Model  2.2.1. Thomson's model  2.2.2. Rutherford's model  2.2.3. Bohr's model  2.3. Quantum mechanical model of the atom  2.4. Dual nature of matter and radiation  2.5. Heisenberg's uncertainty principle  2.6. Quantum numbers  2.7. Atomic orbitals and their shapes  2.8. Electronic configuration of elements  2.9. Aufbau principle  2.10. Pauli's exclusion principle  2.11. Hund's maximum multiplicity rule  2.12. de Broglie's hypothesis  2.13. Photoelectric effect
  3. Classification of elements and periodicity in properties  3.1. Historical development of the periodic table  3.2. Modern Periodic Law and Periodic Table  3.3. Periodic trends in properties  3.3.1. Atomic and Ionic Radius  3.3.2. Ionization enthalpy  3.3.3. Electron gain enthalpy  3.3.4. Electronegativity  3.3.5. Valency  3.3.6. Metallic and Non-Metallic Properties  3.3.7. Oxidation states  3.4. Unusual Properties of the First Elements
  4. Chemical Bonding and Molecular Structure  4.1. Kossel–Lewis approach to chemical bonding  4.2. Ionic or electrovalent bond  4.3. Covalent bond and its features  4.4. Bond parameters  4.5. VSEPR Theory  4.6. Valence bond theory  4.7. Hybridization and its types  4.8. Molecular orbital theory  4.8.1. Bond order and stability  4.9. Hydrogen bonding
  5. States of matter  5.1. Intermolecular forces  5.2. Gas Laws  5.2.1. Boyle's law  5.2.2. Charles's Law  5.2.3. Avogadro's Law  5.2.4. Dalton's law of partial pressure  5.2.5. Graham's law of spread  5.3. Ideal Gas Equation and Applications  5.4. Real gases and deviations from ideal behaviour  5.5. Kinetic molecular theory of gases  5.6. Liquefaction of gases  5.7. Properties of Liquids  5.8. Surface tension and viscosity
  6. Thermodynamics  6.1. System and environment  6.2. Types of systems in thermodynamics  6.3. Types of procedures  6.4. First law of thermodynamics  6.5. Internal energy and enthalpy  6.6. Heat capacity and specific heat  6.7. Hess's law of constant heat summation  6.8. Bond dissociation enthalpy  6.9. Enthalpy of formation and combustion  6.10. Enthalpy of solution and neutralization  6.11. Spontaneity and the second law of thermodynamics  6.12. Gibbs free energy and its applications
  7. Balance  7.1. The concept of balance  7.2. Equilibrium constant and its applications  7.3. Le Chatelier's principle  7.4. Ionic equilibrium in solutions  7.5. Acid and Base Theory  7.5.1. Arrhenius concept  7.5.2. Bronsted-Lowry concept  7.5.3. Lewis concept  7.6. pH Scale and pOH  7.7. Common ion effect  7.8. Hydrolysis of salts  7.9. Buffer solutions and their mechanism of action  7.10. Solubility equilibrium of sparingly soluble salts
  8. Redox reactions  8.1. Oxidation and reduction concepts  8.2. Oxidation number and its applications  8.3. Redox reactions in terms of electron transfer  8.4. Balancing redox reactions (oxidation number and ion-electron methods)  8.5. Types of redox reactions  8.6. Electrochemical Cells and Redox Reactions
  9. Hydrogen  9.1. Position of Hydrogen in the Periodic Table  9.2. Isotopes of hydrogen  9.3. Preparation of Hydrogen  9.4. Properties of Hydrogen  9.5. Hydrides and their classification  9.6. Water and heavy water  9.7. Hydrogen peroxide and its properties  9.8. Uses of Hydrogen and Its Compounds
  10. S-block elements (alkali and alkaline earth metals)  10.1. Group 1 Elements - Properties and Trends  10.2. Group 2 Elements - Properties and Trends  10.3. Unusual properties of lithium and beryllium  10.4. Important compounds of sodium and their uses  10.5. Important Compounds of Magnesium and Calcium
  11. Some p-block elements  11.1. General Introduction to p-Block Elements  11.2. Group 13 Elements  11.2.1. Boron and its compounds  11.3. Group 14 Elements  11.3.1. Carbon and its allotropes  11.3.2. Important Compounds of Carbon and Silicon
  12. Organic Chemistry - Some Basic Principles and Techniques  12.1. Classification and Nomenclature of Organic Compounds  12.2. Structural representation of organic compounds  12.3. Classification of organic reactions  12.4. Electronic Effects in Organic Chemistry  12.4.1. Inductive effect  12.4.2. Resonance effect  12.4.3. Hyperconjugation  12.5. Reaction mechanism and intermediate species  12.6. Purification and qualitative analysis of organic compounds
  13. Hydrocarbons  13.1. Hydrocarbons  13.1.1. Preparation and Properties of Alkenes  13.2. alkene  13.2.1. Preparation and Properties of Alkenes  13.2.2. Electrophilic addition reactions  13.3. Alkynes  13.3.1. Preparation and Properties of Alkynes  13.4. Aromatic hydrocarbons  13.4.1. Structure and properties of benzene  13.4.2. Electrophilic substitution reactions of benzene
  14. Environmental Chemistry  14.1. Environmental Pollution  14.2. Atmospheric pollution and the greenhouse effect  14.3. Water pollution and treatment methods  14.4. Soil pollution and its effects  14.5. Industrial waste and its treatment  14.6. Strategies for pollution control

Grade 11 → Organic Chemistry - Some Basic Principles and Techniques ↓


Purification and qualitative analysis of organic compounds


Organic compounds form the basis of life on Earth, and their study is essential to understanding chemistry. Organic chemistry is primarily concerned with the structure, properties, and reactions of organic compounds, which contain carbon in covalent bonds. This document explains the processes of purification and qualitative analysis, which are essential skills in organic chemistry.

Purification of organic compounds

Organic synthesis often produces products with impurities, which can interfere with their properties or further reactions. Therefore, purification is an important step. Common methods of purification include:

1. Filtration

Filtration separates solids from liquids or gases using a filter medium. It is often used when a reaction produces a solid precipitate. An example of this would be separating PbCl 2 crystals from a liquid mixture.

2. Crystallization

Crystallization helps to purify solid compounds. It involves dissolving a solid substance in a hot solvent to form a solution and slowly cooling it to form pure crystals. These crystals can then be collected through filtration. For example, benzoic acid can be purified using this method.

3. Distillation

Distillation is used to separate components based on different boiling points. For example, a mixture of acetone (CH 3 COCH 3) and water can be separated by distillation because of their different boiling points.

 Distillation Equipment: , , | Condenser | , , Boiling Flask Receiver

4. Sublimation

Sublimation is used for substances that change from a solid to a gas without passing through the liquid state. It is useful for purifying substances such as iodine (I 2) and naphthalene.

5. Chromatography

Chromatography separates mixtures based on differences in their speed through the stationary phase. Thin layer chromatography (TLC) is a simple method where components move at different rates on a coated glass plate.

 Chromatography Example: |-------------| (starting line) , | AB | (spots of different samples) , |................ (Solvent Front) , | A' B' | (spaces separated)

Qualitative analysis

Qualitative analysis identifies the components in a given organic compound. The main steps and methods are as follows:

1. Trace elements

Common elements in organic compounds are carbon, hydrogen, oxygen, nitrogen, sulfur, and halogens. Several tests help determine their presence:

Detection of carbon and hydrogen

Carbon and hydrogen can be tested by heating the compound in the presence of CuO. Carbon is converted to CO 2, which turns lime water milky, while hydrogen is converted to H 2 O, which condenses.

Nitrogen detection

The Lassaigne test involves melting the organic compound with sodium. A typical test would involve:

 Na + C + N → NaCN (sodium cyanide)

Prussian blue colour indicates the presence of nitrogen when NaCN reacts with ferrous sulphate and ferric chloride.

Detection of halogens

Copper wire is used in the Beilstein test. It turns green in the flame due to the presence of halogens such as chlorine, bromine, or iodine.

Detection of sulfur

Sulfur is detected using sodium fusion and sodium nitroprusside, which turns purple in the presence of sulfur.

2. Identification of functional groups

Functional groups define the class and properties of organic compounds. Here are some common groups and their tests:

Functional group: Alcohol

Alcohols such as ethyl alcohol react with sodium to form hydrogen gas, which is embrittled.

Functional group: Aldehyde

Silver nitrate and ammonia are used in the Tollens test. In the presence of aldehyde, a silver mirror is formed inside the test tube.

Functional group: Carboxylic acid

These acids react with sodium bicarbonate to produce carbon dioxide.

Conclusion

Understanding the purification and qualitative analysis of organic compounds is a cornerstone of organic chemistry. Proper purification ensures that compounds retain desired properties, while qualitative analysis reveals element composition and functional groups, providing insight into chemical behavior and reactions.


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