ISC Class 12 Chemistry: Solid State

• Chemistry for Indian School Certificate (ISC) Class 12 covers a range of topics
• The curriculum aims to provide a comprehensive understanding of chemical principles and their applications

Solid State

• Crystalline solids feature a long-range order, whereas amorphous solids lack it.
• Crystalline solids can be classified into molecular, ionic, metallic, and covalent networks.
• Crystal lattices are defined by unit cell parameters 'a', 'b', 'c' and angles α, β, γ.
• Seven crystal systems include cubic, tetragonal, orthorhombic, monoclinic, triclinic, hexagonal, and rhombohedral forms.
• Packing efficiency is the percentage of space occupied by constituent particles.
• Simple cubic cells have a 52.4% packing efficiency.
• Body-centered cubic (bcc) cells have a 68% packing efficiency.
• Face-centered cubic (fcc) cells have a 74% packing efficiency.
• Point defects include vacancies and interstitials.
• Impurity defects occur due to foreign atoms.
• Non-stoichiometric defects include both metal excess and metal deficiency.
• Electrical properties: conductors, semiconductors (n-type and p-type), and insulators.
• Magnetic properties include paramagnetism, diamagnetism, ferromagnetism, antiferromagnetism, and ferrimagnetism.

Solutions

• Solutions are homogeneous mixtures.
• Molarity (M) is defined as moles of solute per liter of solution.
• Molality (m) is defined as moles of solute per kilogram of solvent.
• Mole fraction (x) is the ratio of moles of a component to the total moles in the solution.
• Henry's law states that the partial pressure of a gas is proportional to its mole fraction in the solution.
• Raoult's law states that the vapor pressure of a solution is directly proportional to the mole fraction of the solvent.
• Ideal solutions obey Raoult's law across all concentrations.
• Positive deviations from Raoult's law indicate weaker solute-solvent interactions.
• Negative deviations suggest stronger solute-solvent interactions.
• Azeotropes are constant boiling mixtures that cannot be separated via simple distillation.
• Colligative properties are determined by the number of solute particles.
• Relative lowering of vapor pressure: ΔP/P° = x₂ (mole fraction of solute).
• Elevation of boiling point: ΔT_b = K_b * m, where K_b is the ebullioscopic constant.
• Depression of freezing point: ΔT_f = K_f * m, where K_f is the cryoscopic constant.
• Osmotic pressure: π = CRT, where C is the molar concentration, R is the gas constant, and T is the temperature.
• Van't Hoff factor (i) accounts for the dissociation or association of solute particles.
• i = 1 for non-electrolytes.
• i > 1 indicates dissociation; i < 1 indicates association.
• Abnormal molar masses are obtained when i ≠ 1.

Electrochemistry

• Electrochemical cells convert chemical energy into electrical energy, and vice versa.
• Electrolytic cells use electrical energy to drive non-spontaneous reactions.
• Galvanic cells (voltaic cells) generate electricity from spontaneous redox reactions.
• Oxidation occurs at the anode (negative in galvanic cell, positive in electrolytic cell).
• Reduction occurs at the cathode (positive in galvanic cell, negative in electrolytic cell).
• Standard electrode potential (E°) is the potential of an electrode under standard conditions.
• The Nernst equation relates electrode potential to concentration and temperature: E = E° - (RT/nF)lnQ.
• Gibbs free energy change: ΔG = -nFE.
• ΔG° = -nFE°.
• Equilibrium constant: ΔG° = -RTlnK, E° = (RT/nF)lnK.
• Electrolysis decomposes an electrolyte by the passing of electricity.
• Faraday's laws of electrolysis: mass deposited is proportional to charge passed.
• Conductivity (κ) measures a solution's ability to conduct electricity: κ = 1/ρ (ρ = resistivity).
• Molar conductivity (Λ_m) is the conductivity of a solution containing 1 mole of electrolyte.
• Λ_m = κ/C, where C is the molar concentration.
• Kohlrausch's law states that the limiting molar conductivity of an electrolyte is the sum of individual ion contributions.
• Batteries can be primary (non-rechargeable), secondary (rechargeable), or fuel cells.

Chemical Kinetics

• Chemical kinetics studies reaction rates and reaction mechanisms.
• The rate of reaction is the change in reactant or product concentration per unit time.
• The rate law expresses the rate of reaction in terms of reactant concentrations.
• Rate = k[A]^m[B]^n, where k is the rate constant, m and n are the orders with respect to A and B.
• The order of reaction is the sum of the exponents in the rate law (m + n).
• Molecularity is the number of reacting species in an elementary reaction.
• Integrated rate laws relate reactant concentration to time.
• Zero-order: [A] = [A]₀ - kt.
• First-order: ln[A] = ln[A]₀ - kt.
• Second-order: 1/[A] = 1/[A]₀ + kt.
• Half-life (t₁/₂) represents the time taken for the reactant concentration to halve.
• The Arrhenius equation relates the rate constant to temperature: k = Ae^(-Ea/RT).
• Activation energy (Ea) is the minimum energy needed for a reaction.
• 'A' stands for the frequency factor.
• Catalysts change the rate of reaction without being consumed.
• Homogeneous catalysts exist in the same phase as reactants.
• Heterogeneous catalysts are in a different phase.

Surface Chemistry

• Surface chemistry studies phenomena at surfaces or interfaces.
• Adsorption is the accumulation of a substance on the surface of another.
• Adsorbate is the substance being adsorbed, and adsorbent is the substance on whose surface adsorption occurs.
• Physisorption (physical adsorption) involves weak van der Waals forces.
• Chemisorption (chemical adsorption) involves chemical bonds.
• Factors affecting adsorption: surface area, temperature, and pressure.
• Freundlich adsorption isotherm: x/m = kP^(1/n).
• Langmuir adsorption isotherm: x/m = (aP)/(1 + bP).
• Catalysis: homogeneous and heterogeneous types.
• Enzymes are biological catalysts.
• Colloids are heterogeneous systems with particle sizes between 1 and 1000 nm.
• Lyophilic colloids are solvent-loving.
• Lyophobic colloids are solvent-hating.
• Emulsions are liquid-liquid colloids.
• Gels are liquid dispersed in solid, smokes are solid dispersed in gas.
• Micelles form by association of colloids in solution.
• Cleansing action of soaps involves micelle formation.

General Principles and Processes of Isolation of Elements

• Elements can be found in combined and native forms.
• Concentration of ores removes unwanted materials (gangue).
• Methods: hydraulic washing, magnetic separation, froth floatation, leaching.
• Extraction of metals relies on reduction of concentrated ore.
• Refining of metals purifies them.
• Specific extraction methods exist for aluminum, copper, zinc, and iron.

p-Block Elements

• Group 15 elements: nitrogen family (N, P, As, Sb, Bi).
• Nitrogen's unique properties arise from its small size and high electronegativity.
• Ammonia (NH₃): preparation, properties, uses.
• Nitric acid (HNO₃): Ostwald's process, properties, uses.
• Oxides of nitrogen.
• Phosphorus allotropic forms: white, red, black.
• Phosphine (PH₃), phosphorus halides, oxoacids of phosphorus.
• Group 16 elements: oxygen family (O, S, Se, Te, Po).
• Ozone (O₃): preparation, properties, uses.
• Sulfur allotropic forms.
• Sulfur dioxide (SO₂): preparation, properties, uses.
• Sulfuric acid (H₂SO₄): Contact process, properties, uses.
• Oxoacids of sulfur.
• Group 17 elements: halogens (F, Cl, Br, I, At).
• Chlorine (Cl₂): preparation, properties, uses.
• Hydrogen chloride (HCl): preparation, properties, uses.
• Oxoacids of halogens.
• Interhalogen compounds.
• Group 18 elements: noble gases (He, Ne, Ar, Kr, Xe, Rn).
• Inertness due to complete octet.
• Xenon compounds: XeF₂, XeF₄, XeF₆.

d- and f-Block Elements

• d-block elements are transition elements.
• f-block elements are inner transition elements (lanthanides and actinides).
• Electronic configuration, metallic character, ionization enthalpy, oxidation states.
• Variable oxidation states are characteristic.
• Catalytic properties arise from variable oxidation states and surface area.
• Colored ions result from d-d transitions.
• Complex compounds form due to available d-orbitals.
• Magnetic properties: paramagnetism, diamagnetism.
• Interstitial compounds.
• Alloy formation.
• Lanthanide contraction.
• Actinides.

Coordination Compounds

• Coordination compounds contain a central metal atom/ion surrounded by ligands.
• Ligands are molecules/ions that donate electron pairs to the metal.
• Coordination number is the number of ligands attached to the metal.
• Werner's theory explains the structure of coordination compounds.
• IUPAC nomenclature.
• Isomerism: structural (ionization, hydrate, linkage) & stereoisomerism (geometrical, optical).
• Bonding: valence bond theory (VBT), crystal field theory (CFT).
• VBT explains magnetic properties and geometry.
• CFT explains the splitting of d-orbitals.
• The spectrochemical series ranks ligands by splitting power.
• Coordination compounds have applications in medicine, analysis, and industry.

Haloalkanes and Haloarenes

• Haloalkanes (alkyl halides) have a halogen atom bonded to an alkyl group.
• Haloarenes (aryl halides) have a halogen atom bonded to an aryl group.
• Nomenclature, physical properties, chemical reactions.
• SN1 and SN2 reactions, their mechanisms, and factors affecting reactivity.
• Elimination reactions.
• Reactions with metals.
• Haloarenes: preparation, chemical reactions.
• Nucleophilic substitution reactions in haloarenes are less reactive.
• Electrophilic substitution reactions.
• Polyhalogen compounds: dichloromethane, chloroform, iodoform, carbon tetrachloride, freons, DDT.

Alcohols, Phenols, and Ethers

• Alcohols contain an -OH group bonded to an alkyl group.
• Phenols contain an -OH group bonded to an aryl group.
• Ethers feature an oxygen atom bonded to two alkyl/aryl groups.
• Nomenclature, physical properties, chemical reactions.
• Acidity of alcohols and phenols.
• Reactions of alcohols: esterification, oxidation, dehydration.
• Reactions of phenols: electrophilic substitution.
• Williamson ether synthesis.
• Reactions of ethers.

Aldehydes, Ketones, and Carboxylic Acids

• Aldehydes have a C=O bonded to one alkyl/aryl group and one hydrogen atom.
• Ketones have a C=O bonded to two alkyl/aryl groups.
• Carboxylic acids contain a -COOH group.
• Nomenclature, physical properties, chemical reactions.
• Nucleophilic addition reactions of aldehydes and ketones.
• Oxidation of aldehydes and ketones.
• Reduction of aldehydes and ketones.
• Reactions of carboxylic acids: acidity, esterification, reduction, decarboxylation.
• Hell-Volhard-Zelinsky reaction.

Amines

• Amines are derivatives of ammonia (NH₃).
• Primary (R-NH₂), secondary (R₂-NH), and tertiary (R₃-N) amines.
• Nomenclature, physical properties, chemical reactions.
• Basicity of amines.
• Reactions with nitrous acid.
• Diazonium salts: preparation, chemical reactions.
• Gabriel phthalimide synthesis.

Biomolecules

• Carbohydrates include monosaccharides, disaccharides, and polysaccharides.
• Examples: glucose, fructose, sucrose, starch, cellulose.
• Proteins: amino acids, peptide bonds, primary, secondary, tertiary, and quaternary structures.
• Denaturation of proteins.
• Enzymes are biological catalysts.
• Vitamins can be fat-soluble or water-soluble.
• Nucleic acids: DNA and RNA.
• DNA structure and replication.

Polymers

• Polymers consist of repeating structural units (monomers).
• Classification: natural, synthetic, addition, condensation, homopolymers, copolymers.
• Polymerization reactions: addition and condensation.
• Examples: polyethylene, polypropylene, PVC, Teflon, Bakelite, nylon, polyester.

Chemistry in Everyday Life

• Drugs: analgesics, tranquilizers, antiseptics, disinfectants, antibiotics, antacids, antihistamines.
• Food preservatives.
• Artificial sweetening agents.
• Soaps and detergents.

This lesson covers the solid state chapter for Indian School Certificate (ISC) Class 12 Chemistry. It includes crystalline and amorphous solids, crystal lattices, unit cells, packing efficiency, and defects. Learn about the different types of crystal systems and their properties.