Topics
Some Basic Concepts of Chemistry
Introduction to Analytical Chemistry
- Introduction of Analytical Chemistry
- Analysis
- Mathematical Operation and Error Analysis
- Determination of Molecular Formula
- Chemical Reactions and Stoichiometric Calculations
- Limiting Reagent
- Concentration of a Solution
- Use of Graph in Analysis
Basic Analytical Techniques
- Introduction of Some Analytical Techniques
- Purification of Solids
- Crystallisation Method
- Fractional Crystallization
- Simple Distillation Method
- Solvent Extraction
- Chromatography Method
- Chromatography Method > Adsorption Chromatography
- Chromatography Method > Partition Chromatography
Structure of Atom
Chemical Bonding
- Concept of Chemical Bonding
- Kossel-lewis Approach to Chemical Bonding - Octet Rule
- Kossel and Lewis Approach to Chemical Bonding
- Formal Charge
- Limitations of the Octet Rule
- Valence Shell Electron Pair Repulsion (VSEPR) Theory
- Valence Bond Theory (VBT)
- Molecular Orbital Theory
- Parameters of Covalent Bond
- Dipole Moment
- Resonance
Redox Reactions
Modern Periodic Table
- Introduction of Periodic Table
- Structure of the Modern Periodic Table
- Periodic Table and Electronic Configuration
- Blockwise Characteristics of Elements
- Periodic Trends in Elemental Properties
Elements of Group 1 and 2
Elements of Group 13, 14 and 15
- Electronic Configuration of Elements of Groups 13, 14 and 15
- Trends in Atomic and Physical Properties of Elements of Groups 13, 14 and 15
- Chemical Properties of the Elements of the Groups 13,14 and 15
- Carbon: A Versatile Element
- Allotropes of Carbon > Diamond
- Molecular Structures of Some Important Compounds of the Group 13, 14 and 15 Elements
- Chemistry of Notable Compounds of Elements of Groups 13, 14 and 15
States of Matter
- States of Matter
- Intermolecular Forces
- Characteristic Properties of Gases
- Gas Laws
- Ideal Gas Equation
- Kinetic Molecular Theory of Gases
- Deviation from Ideal Behaviour
- Liquefaction of Gases and Critical Constant
- Liquid State
Adsorption and Colloids
- Introduction of Adsorption
- Adsorption
- Types of Adsorption
- Factors Affecting Adsorption of Gases on Solids
- Adsorption Isotherms (Freundlich and Langmuir Adsorption Isotherm)
- Applications of Adsorption
- Catalysis
- Adsorption Theory of Heterogeneous Catalysis
- Colloids
Chemical Equilibrium
- Introduction of Chemical Equilibrium
- Equilibrium in Physical Processes
- Equilibrium in Chemical Processes - Dynamic Equilibrium
- Law of Mass Action and Equilibrium Constant
- Homogeneous and Heterogenous Equilibria
- Characteristics of Equilibrium Constant
- Applications of Equilibrium Constants
- Le Chaterlier's Principle and Factors Altering the Composition of Equilibrium
- Industrial Application
Nuclear Chemistry and Radioactivity
- Introduction: Nuclear Chemistry is a Branch of Physical Chemistry
- Classification of Nuclides
- Nuclear Stability
- Radioactivity
- Radioactive Decays
- Modes of Decay
- Nuclear Reactions
- Applications of Radio Isotopes
Basic Principles of Organic Chemistry
- Organic Chemistry
- Structural Representation of Organic Molecules
- Classification of Organic Compounds
- Nomenclature
- Isomerism
- Theoretical Basis of Organic Reactions
Hydrocarbons
Chemistry in Everyday Life
- Chemistry in Everyday Life
- Basics of Food Chemistry
- Compounds with Medicinal Properties
- Cleansing Agents
Estimated time: 9 minutes
Maharashtra State Board: Class 12
Key Points: Molecular Orbital Theory
Molecular orbitals (MOs) are formed by the linear combination of atomic orbitals (LCAO).
Two types of MOs form:
- Bonding MOs — lower energy than the original atomic orbitals; electrons here stabilise the molecule (σ, π)
- Antibonding MOs — higher energy; electrons here destabilise the molecule (σ*, π*)
Energy Order of MOs for Diatomic Molecules:
For O₂, F₂ (electrons > 14):
σ1s < σ∗1s < σ2s < σ∗2s < σ2pz < (π2px = π2py) < (π∗2px = π∗2py) < σ∗2pz
For B₂, C₂, N₂ (electrons ≤ 14):
σ1s < σ∗1s < σ2s < σ∗2s < (π2px = π2py)< σ2pz < (π∗2px = π∗2py) < σ∗2pz
Electronic Configurations and Bond Properties of Diatomic Molecules:
| Molecule | Electronic Configuration | Bond Order | Magnetic Nature |
|---|---|---|---|
| H₂ | (σ1s)² | 1 | Diamagnetic |
| Li₂ | (σ1s)²(σ1s)²(σ2s)² | 1 | Diamagnetic |
| N₂ | (σ1s)²(σ1s)²(σ2s)²(σ2s)²(π2p_x)²(π2p_y)²(σ2p_z)² | 3 | Diamagnetic |
| O₂ | (σ1s)²(σ1s)²(σ2s)²(σ2s)²(σ2p_z)²(π2p_x)²(π2p_y)²(π2p_x)¹(π2p_y)¹ | 2 | Paramagnetic |
| F₂ | (σ1s)²(σ1s)²(σ2s)²(σ2s)²(σ2p_z)²(π2p_x)²(π2p_y)²(π2p_x)²(π2p_y)² | 1 | Diamagnetic |
Maharashtra State Board: Class 12
Formula: Bond Order
\[\mathrm{Bond~Order}=\frac{N_b-N_a}{2}\]
where Nb = number of electrons in bonding MOs, Na = number of electrons in antibonding MOs.
-
Bond order > 0 → molecule is stable
-
Bond order = 0 or negative → molecule is unstable (does not exist)
Maharashtra State Board: Class 12
Formula: Magnetic Moment
\[\mu=\sqrt{n(n+2)}\text{BM (Bohr Magneton)}\]
where n = number of unpaired electrons. If any unpaired electron is present → paramagnetic; if none → diamagnetic.
