JEE Mains Reaction Compendium

Cheatsheet Content

### Organic Reactions (Name Reactions) - **Wurtz Reaction:** $R-X + Na + X-R \xrightarrow{Dry\ Ether} R-R + 2NaX$ (for alkanes) - **Wurtz-Fittig Reaction:** $Ar-X + Na + X-R \xrightarrow{Dry\ Ether} Ar-R + 2NaX$ (for alkylarenes) - **Fittig Reaction:** $Ar-X + Na + X-Ar \xrightarrow{Dry\ Ether} Ar-Ar + 2NaX$ (for biphenyls) - **Kolbe's Electrolysis:** $2R-COONa \xrightarrow{Electrolysis} R-R + 2CO_2 + 2NaOH + H_2$ (for alkanes) - **Frankland Reaction:** $R-X + Zn + X-R \xrightarrow{} R-R + ZnX_2$ (similar to Wurtz) - **Corey-House Synthesis:** $R-X + Li \xrightarrow{Dry\ Ether} RLi \xrightarrow{CuI} R_2CuLi \xrightarrow{R'-X} R-R'$ (for unsymmetrical alkanes) - **Friedel-Crafts Alkylation:** $Ar-H + R-X \xrightarrow{AlCl_3\ (anhydrous)} Ar-R + HX$ - **Friedel-Crafts Acylation:** $Ar-H + R-COCl \xrightarrow{AlCl_3\ (anhydrous)} Ar-COR + HCl$ - **Gattermann Reaction (for aldehydes):** $C_6H_5CN + HCl \xrightarrow{AlCl_3\ (anhydrous)} C_6H_5CHO$ - **Gattermann-Koch Reaction:** $Ar-H + CO + HCl \xrightarrow{AlCl_3/CuCl} Ar-CHO$ - **Reimer-Tiemann Reaction:** Phenol $\xrightarrow{CHCl_3/NaOH} o/p$-Hydroxybenzaldehyde - **Kolbe's Reaction (for phenols):** Phenol $\xrightarrow{CO_2/NaOH} Salicylic\ Acid$ - **Rosenmund Reduction:** $R-COCl \xrightarrow{H_2/Pd-BaSO_4} R-CHO$ (acid chlorides to aldehydes) - **Stephen Reaction:** $R-CN \xrightarrow{SnCl_2/HCl} R-CH=NH \xrightarrow{H_3O^+} R-CHO$ (nitriles to aldehydes) - **Etard Reaction:** Toluene $\xrightarrow{CrO_2Cl_2} Chromyl\ Complex \xrightarrow{H_3O^+} Benzaldehyde$ - **Cannizzaro Reaction:** Aldehydes (no $\alpha$-H) $\xrightarrow{Conc.\ NaOH} Alcohol + Carboxylate$ - **Aldol Condensation:** Aldehydes/Ketones (with $\alpha$-H) $\xrightarrow{Dil.\ NaOH} \beta$-Hydroxyaldehyde/Ketone $\xrightarrow{\Delta} \alpha,\beta$-Unsaturated\ Carbonyl - **Clemmensen Reduction:** Carbonyl compound $\xrightarrow{Zn-Hg/Conc.\ HCl} Alkane$ - **Wolff-Kishner Reduction:** Carbonyl compound $\xrightarrow{NH_2NH_2/KOH/Ethylene\ Glycol} Alkane$ - **Perkin Reaction:** Aromatic aldehyde + Acetic anhydride + Sodium acetate $\xrightarrow{\Delta} \alpha,\beta$-Unsaturated\ Carboxylic\ Acid - **Knoevenagel Condensation:** Aldehyde/Ketone + Active Methylene Compound $\xrightarrow{Base} \alpha,\beta$-Unsaturated\ Compound - **Hell-Volhard-Zelinsky (HVZ) Reaction:** $R-CH_2-COOH \xrightarrow{X_2/Red\ P} R-CH(X)-COOH$ - **Hofmann Bromamide Degradation:** $R-CONH_2 \xrightarrow{Br_2/KOH} R-NH_2 + K_2CO_3 + KBr + H_2O$ (amide to primary amine, one C less) - **Gabriel Phthalimide Synthesis:** Phthalimide $\xrightarrow{KOH} Potassium\ Phthalimide \xrightarrow{R-X} N-Alkylphthalimide \xrightarrow{H_2O/H^+\ or\ H_2N-NH_2} R-NH_2$ (for primary amines) - **Carbylamine Reaction (Isocyanide Test):** Primary amine $\xrightarrow{CHCl_3/KOH} Isocyanide\ (foul\ smell)$ - **Mendius Reaction:** $R-CN \xrightarrow{Na/C_2H_5OH} R-CH_2-NH_2$ (reduction of nitriles) - **Stephen Reduction (alternate):** $R-CN \xrightarrow{SnCl_2/HCl} R-CHO$ (already listed, but important) - **Sandmeyer Reaction:** $Ar-N_2^+X^- \xrightarrow{CuX/HX} Ar-X + N_2$ (X = Cl, Br, CN) - **Gattermann Reaction (for halides):** $Ar-N_2^+X^- \xrightarrow{Cu/HX} Ar-X + N_2$ (X = Cl, Br) - **Balz-Schiemann Reaction:** $Ar-N_2^+BF_4^- \xrightarrow{\Delta} Ar-F + BF_3 + N_2$ - **Diazotization:** $Ar-NH_2 \xrightarrow{NaNO_2/HCl,\ 0-5^\circ C} Ar-N_2^+Cl^-$ - **Coupling Reaction:** $Ar-N_2^+Cl^- + Phenol/Aniline \xrightarrow{Weakly\ Acidic/Alkaline} Azo\ Dye$ - **Schmidt Reaction:** Carboxylic acid $\xrightarrow{NaN_3/H_2SO_4} Primary\ Amine$ - **Curtius Rearrangement:** Acyl Azide $\xrightarrow{\Delta} Isocyanate \xrightarrow{H_2O} Primary\ Amine$ - **Schotten-Baumann Reaction:** Acylation of amines/phenols with acid chloride/anhydride in presence of base. - **Birch Reduction:** Benzene $\xrightarrow{Na/Liquid\ NH_3/C_2H_5OH} 1,4-Cyclohexadiene$ - **Baeyer-Villiger Oxidation:** Ketone $\xrightarrow{Peroxyacid} Ester$ - **Williamson Ether Synthesis:** $R-ONa + R'-X \xrightarrow{} R-O-R' + NaX$ - **Swern Oxidation:** Primary alcohol $\xrightarrow{(COCl)_2/DMSO} Aldehyde$ - **PCC Oxidation:** Primary alcohol $\xrightarrow{PCC} Aldehyde$ - **DCC Oxidation:** Primary alcohol $\xrightarrow{DCC/DMSO} Aldehyde$ - **Oppenauer Oxidation:** Secondary alcohol $\xrightarrow{Al(O-t-Bu)_3/Acetone} Ketone$ - **Meerwein-Ponndorf-Verley (MPV) Reduction:** Aldehyde/Ketone $\xrightarrow{Al(O-i-Pr)_3/Isopropanol} Alcohol$ - **Darzens Reaction (Glycidic Ester Condensation):** Aldehyde/Ketone + $\alpha$-haloester $\xrightarrow{Base} \alpha,\beta$-Epoxy ester - **Wittig Reaction:** Aldehyde/Ketone + Phosphonium Ylide $\xrightarrow{} Alkene$ - **Reformatsky Reaction:** Aldehyde/Ketone + $\alpha$-bromoester + Zn $\xrightarrow{} \beta$-Hydroxyester - **Arndt-Eistert Synthesis:** Carboxylic acid $\xrightarrow{SOCl_2} R-COCl \xrightarrow{CH_2N_2} R-CO-CHN_2 \xrightarrow{Ag_2O/H_2O} R-CH_2-COOH$ (chain lengthening) ### Organic Reactions (Functional Group Transformations) #### Alkanes - **Halogenation (Free Radical):** $R-H + X_2 \xrightarrow{hv\ or\ \Delta} R-X + HX$ - **Combustion:** $C_nH_{2n+2} + O_2 \xrightarrow{} CO_2 + H_2O$ #### Alkenes & Alkynes - **Hydrogenation:** $C=C\ or\ C\equiv C \xrightarrow{H_2/Ni,Pd,Pt} Alkane$ - **Hydrohalogenation (Markovnikov):** $C=C + HX \xrightarrow{} Alkyl\ Halide$ - **Hydrohalogenation (Anti-Markovnikov):** $C=C + HBr \xrightarrow{Peroxide} Alkyl\ Bromide$ - **Hydration (Acid-catalyzed):** $C=C \xrightarrow{H_2O/H^+} Alcohol$ (Markovnikov) - **Oxymercuration-Demercuration:** $C=C \xrightarrow{Hg(OAc)_2/H_2O \ then\ NaBH_4} Alcohol$ (Markovnikov) - **Hydroboration-Oxidation:** $C=C \xrightarrow{BH_3/THF \ then\ H_2O_2/OH^-} Alcohol$ (Anti-Markovnikov) - **Halogenation:** $C=C + X_2 \xrightarrow{CCl_4} Vicinal\ Dihalide$ - **Halohydrin Formation:** $C=C + X_2/H_2O \xrightarrow{} Halohydrin$ - **Ozonolysis (Reductive):** $C=C \xrightarrow{O_3 \ then\ Zn/H_2O} Aldehydes/Ketones$ - **Ozonolysis (Oxidative):** $C=C \xrightarrow{O_3 \ then\ H_2O_2} Carboxylic\ Acids/Ketones$ - **Baeyer's Reagent (Cold, Dilute Alkaline KMnO$_4$):** $C=C \xrightarrow{KMnO_4/OH^-/Cold} Vicinal\ Diol$ (Syn addition) - **Hot Acidic KMnO$_4$:** $C=C \xrightarrow{KMnO_4/H^+/\Delta} Carboxylic\ Acids/Ketones/CO_2$ (cleavage) - **Polymerization:** $n(C=C) \xrightarrow{Catalyst/\Delta/P} Polyalkene$ - **Acidity of Terminal Alkynes:** $R-C\equiv CH \xrightarrow{Na/NaNH_2} R-C\equiv C^-Na^+$ #### Alkyl Halides - **Nucleophilic Substitution (SN1/SN2):** $R-X + Nu^- \xrightarrow{} R-Nu + X^-$ - **Elimination (E1/E2):** $R-X + Base \xrightarrow{} Alkene$ (Saytzeff/Hofmann) - **Reaction with Mg:** $R-X + Mg \xrightarrow{Dry\ Ether} R-MgX$ (Grignard Reagent) - **Reaction with Na (Wurtz):** $2R-X + 2Na \xrightarrow{Dry\ Ether} R-R + 2NaX$ #### Alcohols & Phenols - **Oxidation (Primary):** $R-CH_2OH \xrightarrow{PCC} R-CHO \xrightarrow{KMnO_4} R-COOH$ - **Oxidation (Secondary):** $R_2CHOH \xrightarrow{CrO_3\ or\ KMnO_4} R_2CO$ - **Dehydration:** $R-CH_2-CH_2OH \xrightarrow{Conc.\ H_2SO_4/\Delta} Alkene$ - **Reaction with HX:** $R-OH + HX \xrightarrow{} R-X + H_2O$ (Lucas Test for alcohols) - **Esterification:** $R-OH + R'-COOH \xrightarrow{H^+} R'-COOR + H_2O$ - **Acidity of Phenols:** Phenol $\xrightarrow{NaOH} Sodium\ Phenoxide$ - **Electrophilic Substitution (Phenol):** $-\text{OH}$ is activating and o,p-directing. Nitration, Halogenation, Sulfonation. #### Ethers - **Cleavage with HI/HBr:** $R-O-R' \xrightarrow{HI\ or\ HBr} R-I + R'-OH \ or\ R-I + R'-I$ #### Aldehydes & Ketones - **Nucleophilic Addition:** Carbonyl compounds react with HCN, NaHSO$_3$, Grignard reagents, alcohols (acetal/ketal formation), ammonia derivatives. - **Reduction to Alcohols:** $R-CHO \xrightarrow{NaBH_4\ or\ LiAlH_4} Primary\ Alcohol$ - **Reduction to Alcohols:** $R_2CO \xrightarrow{NaBH_4\ or\ LiAlH_4} Secondary\ Alcohol$ - **Oxidation (Aldehydes):** $R-CHO \xrightarrow{Tollens'/Fehling's/KMnO_4} R-COOH$ - **Haloform Reaction:** $CH_3-CO-R$ or $CH_3-CH(OH)-R \xrightarrow{X_2/NaOH} CHX_3 + R-COONa$ - **Acetal/Ketal Formation:** Carbonyl + Alcohol $\xrightarrow{H^+} Acetal/Ketal$ #### Carboxylic Acids & Derivatives - **Acidity:** $R-COOH \xrightarrow{NaOH/NaHCO_3} R-COONa$ - **Esterification:** $R-COOH + R'-OH \xrightarrow{H^+} R-COOR' + H_2O$ - **Reduction:** $R-COOH \xrightarrow{LiAlH_4} R-CH_2OH$ - **Decarboxylation:** $R-COOH \xrightarrow{NaOH/CaO,\ \Delta} Alkane + Na_2CO_3$ - **Formation of Acid Derivatives:** $R-COOH \xrightarrow{SOCl_2\ or\ PCl_5} R-COCl$ - **Hydrolysis of Esters:** $R-COOR' \xrightarrow{H_2O/H^+\ or\ OH^-} R-COOH + R'-OH$ - **Hydrolysis of Amides:** $R-CONH_2 \xrightarrow{H_2O/H^+\ or\ OH^-} R-COOH + NH_3$ - **Hydrolysis of Nitriles:** $R-CN \xrightarrow{H_2O/H^+\ or\ OH^-} R-COOH$ #### Amines - **Basicity:** $R-NH_2 + H_2O \rightleftharpoons R-NH_3^+ + OH^-$ - **Acylation:** $R-NH_2 + R'-COCl \xrightarrow{Base} R-NH-COR'$ - **Alkylation:** $R-NH_2 + R'-X \xrightarrow{} R-NHR' \xrightarrow{} R_2NR' \xrightarrow{} R_3NR'^+X^-$ (can lead to quaternary salts) - **Reaction with Nitrous Acid:** - Primary Aliphatic: $R-NH_2 \xrightarrow{NaNO_2/HCl} R-OH + N_2$ - Primary Aromatic: $Ar-NH_2 \xrightarrow{NaNO_2/HCl} Ar-N_2^+Cl^-$ (Diazotization) - Secondary: $R_2NH \xrightarrow{NaNO_2/HCl} R_2N-N=O$ (N-Nitrosamine, yellow oily) - Tertiary: $R_3N \xrightarrow{NaNO_2/HCl} R_3NH^+Cl^-$ (forms salt) - **Hinsberg Test:** Primary, Secondary, Tertiary amine distinction using Benzene Sulfonyl Chloride. #### Arenes (Benzene and Derivatives) - **Electrophilic Aromatic Substitution:** - **Nitration:** $Ar-H \xrightarrow{Conc. HNO_3/Conc. H_2SO_4} Ar-NO_2$ - **Halogenation:** $Ar-H \xrightarrow{X_2/FeX_3} Ar-X$ - **Sulfonation:** $Ar-H \xrightarrow{Conc. H_2SO_4/\Delta} Ar-SO_3H$ - **Friedel-Crafts Alkylation/Acylation:** (see name reactions) - **Oxidation of Alkylbenzenes:** Alkyl group $\xrightarrow{KMnO_4/H^+} Benzoic\ Acid$ (if at least one benzylic H) ### Inorganic Reactions (Acid-Base & Redox) #### Acid-Base Reactions - **Neutralization:** Acid + Base $\xrightarrow{} Salt + Water$ (e.g., $HCl + NaOH \xrightarrow{} NaCl + H_2O$) - **Reaction of Metal Oxides with Acid:** Basic Oxide + Acid $\xrightarrow{} Salt + Water$ (e.g., $CaO + 2HCl \xrightarrow{} CaCl_2 + H_2O$) - **Reaction of Non-metal Oxides with Base:** Acidic Oxide + Base $\xrightarrow{} Salt + Water$ (e.g., $CO_2 + 2NaOH \xrightarrow{} Na_2CO_3 + H_2O$) - **Amphoteric Oxides/Hydroxides:** React with both acids and bases (e.g., $Al_2O_3$, $ZnO$, $PbO$, $SnO$, $BeO$). - $Al_2O_3 + 6HCl \xrightarrow{} 2AlCl_3 + 3H_2O$ - $Al_2O_3 + 2NaOH \xrightarrow{} 2NaAlO_2 + H_2O$ (Sodium Aluminate) #### Redox Reactions - **Displacement Reactions:** More reactive metal displaces less reactive metal from its salt solution (e.g., $Zn + CuSO_4 \xrightarrow{} ZnSO_4 + Cu$) - **Combustion:** Reaction with oxygen, often producing heat and light. - **Disproportionation Reactions:** A single element is simultaneously oxidized and reduced (e.g., $2H_2O_2 \xrightarrow{} 2H_2O + O_2$, also $3Cl_2 + 6NaOH \xrightarrow{} 5NaCl + NaClO_3 + 3H_2O$ (hot & conc.)) - **Combination Reactions:** Two or more reactants form a single product (e.g., $N_2 + 3H_2 \xrightarrow{} 2NH_3$) - **Decomposition Reactions:** A single reactant breaks down into two or more products (e.g., $CaCO_3 \xrightarrow{\Delta} CaO + CO_2$) #### Important Oxidizing Agents - **KMnO$_4$ (Potassium Permanganate):** Strong oxidizing agent. - Acidic medium: $MnO_4^- \xrightarrow{H^+} Mn^{2+}$ - Neutral/Weakly alkaline medium: $MnO_4^- \xrightarrow{H_2O} MnO_2$ - Strongly alkaline medium: $MnO_4^- \xrightarrow{OH^-} MnO_4^{2-}$ - **K$_2$Cr$_2$O$_7$ (Potassium Dichromate):** Strong oxidizing agent in acidic medium. - Acidic medium: $Cr_2O_7^{2-} \xrightarrow{H^+} Cr^{3+}$ - **Halogens (Cl$_2$, Br$_2$):** Oxidizing agents. - **Conc. H$_2$SO$_4$:** Oxidizes non-metals (C, S, P) and some metals (Cu, Zn). - **Conc. HNO$_3$:** Oxidizes most metals (except noble metals) and non-metals. - **H$_2$O$_2$ (Hydrogen Peroxide):** Can act as both oxidizing and reducing agent. #### Important Reducing Agents - **LiAlH$_4$, NaBH$_4$:** For organic compounds. - **SnCl$_2$/HCl, Zn/HCl:** For reducing nitro compounds to amines, nitriles to aldehydes. - **H$_2$S, SO$_2$:** Can reduce halogens, Fe(III) to Fe(II), etc. - **Metals:** Na, K, Mg, Al, Zn (e.g., in Wurtz reaction, Clemmensen reduction). ### Inorganic Reactions (P-Block Elements) #### Group 13 (Boron Family) - **Borax Bead Test:** $Na_2B_4O_7 \cdot 10H_2O \xrightarrow{\Delta} Na_2B_4O_7 \xrightarrow{\Delta} 2NaBO_2 + B_2O_3$ (glassy bead) - **Reaction of Boric Acid:** $H_3BO_3 \xrightarrow{\Delta} HBO_2 \xrightarrow{\Delta} B_2O_3$ - **Diborane Synthesis:** $2BF_3 + 6LiH \xrightarrow{} B_2H_6 + 6LiF$ - **Hydrolysis of Boron Trihalides:** $BX_3 + 3H_2O \xrightarrow{} H_3BO_3 + 3HX$ #### Group 14 (Carbon Family) - **Producer Gas:** $C + Air \xrightarrow{\Delta} CO + N_2$ - **Water Gas:** $C + H_2O (steam) \xrightarrow{\Delta} CO + H_2$ - **Reaction of CO:** $CO + Cl_2 \xrightarrow{hv} COCl_2$ (Phosgene) - **Silicones:** Hydrolysis and polymerization of alkyl/aryl substituted chlorosilanes ($R_2SiCl_2$). #### Group 15 (Nitrogen Family) - **Haber's Process:** $N_2 + 3H_2 \rightleftharpoons 2NH_3$ - **Ostwald's Process (HNO$_3$ production):** 1. $4NH_3 + 5O_2 \xrightarrow{Pt/Rh\ catalyst} 4NO + 6H_2O$ 2. $2NO + O_2 \xrightarrow{} 2NO_2$ 3. $3NO_2 + H_2O \xrightarrow{} 2HNO_3 + NO$ - **Phosphorus Allotropes:** White P (highly reactive), Red P, Black P. - **Reaction of PCl$_5$:** $PCl_5 \xrightarrow{H_2O} POCl_3 \xrightarrow{H_2O} H_3PO_4$ - **Reaction of PH$_3$ (Phosphine):** Highly poisonous, burns in air. #### Group 16 (Oxygen Family) - **Contact Process (H$_2$SO$_4$ production):** 1. $S_8 + 8O_2 \xrightarrow{} 8SO_2$ 2. $2SO_2 + O_2 \xrightarrow{V_2O_5\ catalyst} 2SO_3$ 3. $SO_3 + H_2SO_4 \xrightarrow{} H_2S_2O_7$ (Oleum) 4. $H_2S_2O_7 + H_2O \xrightarrow{} 2H_2SO_4$ - **Ozone formation:** $3O_2 \rightleftharpoons 2O_3$ - **H$_2$O$_2$ Decomposition:** $2H_2O_2 \xrightarrow{} 2H_2O + O_2$ (catalyzed by MnO$_2$) #### Group 17 (Halogen Family) - **Deacon's Process (Cl$_2$ production):** $4HCl + O_2 \xrightarrow{CuCl_2\ catalyst} 2Cl_2 + 2H_2O$ - **Reaction of Chlorine with NaOH:** - Cold & Dilute: $Cl_2 + 2NaOH \xrightarrow{} NaCl + NaOCl + H_2O$ - Hot & Concentrated: $3Cl_2 + 6NaOH \xrightarrow{} 5NaCl + NaClO_3 + 3H_2O$ - **Interhalogen Compounds:** $X_2 + Y_2 \xrightarrow{} XY, XY_3, XY_5, XY_7$ - **Bleaching powder:** $Ca(OH)_2 + Cl_2 \xrightarrow{} CaOCl_2 + H_2O$ #### Group 18 (Noble Gases) - Formation of Xenon compounds (XeF$_2$, XeF$_4$, XeF$_6$). - $Xe + F_2 \xrightarrow{673K,\ 1\ bar} XeF_2$ - $Xe + 2F_2 \xrightarrow{873K,\ 7\ bar} XeF_4$ - $Xe + 3F_2 \xrightarrow{573K,\ 60-70\ bar} XeF_6$ - Hydrolysis of Xenon fluorides: - $2XeF_2 + 2H_2O \xrightarrow{} 2Xe + 4HF + O_2$ - $6XeF_4 + 12H_2O \xrightarrow{} 4Xe + 2XeO_3 + 24HF + 3O_2$ ### Inorganic Reactions (D & F-Block Elements) #### D-Block Elements (Transition Metals) - **Variable Oxidation States:** Many transition metals exhibit multiple oxidation states. - **Formation of Colored Ions:** Due to d-d transitions. - **Catalytic Properties:** Many transition metals and their compounds act as catalysts (e.g., V$_2$O$_5$ in Contact Process, Fe in Haber's Process, Ni/Pd/Pt in hydrogenation). - **Formation of Interstitial Compounds:** Non-stoichiometric compounds formed when small atoms (H, C, N) are trapped in the crystal lattice. - **KMnO$_4$ Reactions:** (already covered in Redox, but important for Mn) - **K$_2$Cr$_2$O$_7$ Reactions:** (already covered in Redox, but important for Cr) - **Chromyl Chloride Test:** $K_2Cr_2O_7 + 4NaCl + 6H_2SO_4 \xrightarrow{} 2CrO_2Cl_2\ (red\ vapor) + 2KHSO_4 + 4NaHSO_4 + 3H_2O$ (for Cl$^-$) #### F-Block Elements (Lanthanides & Actinides) - **Lanthanide Contraction:** Gradual decrease in atomic and ionic radii across the series. - **Oxidation States:** Lanthanides primarily show +3, some show +2 and +4. Actinides show a wider range of oxidation states. - **Actinides are Radioactive:** All actinides are radioactive. ### Physical Chemistry (Equilibria & Kinetics) #### Chemical Equilibrium - **Law of Mass Action:** For $aA + bB \rightleftharpoons cC + dD$, $K_c = \frac{[C]^c[D]^d}{[A]^a[B]^b}$ - **Le Chatelier's Principle:** Predicts the shift in equilibrium due to changes in concentration, pressure, temperature. - **Relationship between Kp and Kc:** $K_p = K_c(RT)^{\Delta n_g}$ - **Ionic Equilibrium:** - **Acid-Base Equilibria:** $K_a, K_b$, pH calculations. - **Solubility Product ($K_{sp}$):** For $A_xB_y \rightleftharpoons xA^{y+} + yB^{x-}$, $K_{sp} = [A^{y+}]^x[B^{x-}]^y$. - **Common Ion Effect:** Solubility decreases in presence of common ion. - **Buffer Solutions:** Resist change in pH upon addition of small amounts of acid/base. Henderson-Hasselbalch equation: $pH = pK_a + \log \frac{[Salt]}{[Acid]}$ #### Chemical Kinetics - **Rate Law:** Rate $= k[A]^x[B]^y$ - **Order of Reaction:** Sum of powers of concentration terms in rate law ($x+y$). - **Molecularity:** Number of reacting species in an elementary step. - **Integrated Rate Laws:** - Zero Order: $[A]_t = -kt + [A]_0$ - First Order: $\ln[A]_t = -kt + \ln[A]_0$ or $k = \frac{2.303}{t} \log \frac{[A]_0}{[A]_t}$ - **Half-life ($t_{1/2}$):** - Zero Order: $t_{1/2} = \frac{[A]_0}{2k}$ - First Order: $t_{1/2} = \frac{0.693}{k}$ - **Arrhenius Equation:** $k = Ae^{-E_a/RT}$ or $\ln k = \ln A - \frac{E_a}{RT}$ ### Physical Chemistry (Thermodynamics & Electrochemistry) #### Thermodynamics - **First Law:** $\Delta U = q + w$ - **Enthalpy ($\Delta H$):** $\Delta H = \Delta U + P\Delta V$ at constant pressure. - **Hess's Law:** Enthalpy change is independent of the path. - **Standard Enthalpies:** Formation ($\Delta H_f^\circ$), Combustion ($\Delta H_c^\circ$), Neutralization ($\Delta H_{neut}^\circ$). - **Bond Enthalpy:** $\Delta H_{rxn} = \sum BE_{reactants} - \sum BE_{products}$ - **Second Law:** $\Delta S_{total} = \Delta S_{sys} + \Delta S_{surr} \ge 0$ for a spontaneous process. - **Third Law:** Entropy of a perfect crystalline substance is zero at absolute zero. - **Gibbs Free Energy ($\Delta G$):** $\Delta G = \Delta H - T\Delta S$ - $\Delta G 0$: Non-spontaneous - $\Delta G = 0$: Equilibrium - **Relationship between $\Delta G^\circ$ and K:** $\Delta G^\circ = -RT \ln K$ - **Relationship between $\Delta G$ and Q:** $\Delta G = \Delta G^\circ + RT \ln Q$ #### Electrochemistry - **Electrochemical Cells:** Galvanic (Voltaic) cells and Electrolytic cells. - **Standard Electrode Potential ($E^\circ$):** Reduction potential relative to SHE. - **Nernst Equation:** $E_{cell} = E_{cell}^\circ - \frac{0.0591}{n} \log Q$ (at 298 K) - **Relationship between $E_{cell}^\circ$ and $\Delta G^\circ$:** $\Delta G^\circ = -nFE_{cell}^\circ$ - **Faraday's Laws of Electrolysis:** - First Law: $W = ZIt$ - Second Law: $\frac{W_1}{W_2} = \frac{E_1}{E_2}$ - **Conductance:** $G = \frac{1}{R}$ - **Specific Conductance ($\kappa$):** $\kappa = G \cdot \frac{l}{A}$ - **Molar Conductance ($\Lambda_m$):** $\Lambda_m = \frac{\kappa \times 1000}{M}$ - **Kohlrausch's Law:** $\Lambda_m^\circ = x\lambda_A^\circ + y\lambda_B^\circ$ ### Physical Chemistry (Solutions & Solid State) #### Solutions - **Concentration Terms:** Molarity, Molality, Mole Fraction, Mass %, ppm. - **Henry's Law:** $P = K_H \cdot x$ (solubility of gas in liquid) - **Raoult's Law (for volatile solutes):** $P_A = x_A P_A^\circ$ - **Raoult's Law (for non-volatile solutes):** $\frac{P^\circ - P_s}{P^\circ} = x_{solute}$ (Relative Lowering of Vapor Pressure) - **Colligative Properties:** - **Relative Lowering of Vapor Pressure (RLVP):** $\frac{\Delta P}{P^\circ} = i \cdot x_{solute}$ - **Elevation in Boiling Point ($\Delta T_b$):** $\Delta T_b = i \cdot K_b \cdot m$ - **Depression in Freezing Point ($\Delta T_f$):** $\Delta T_f = i \cdot K_f \cdot m$ - **Osmotic Pressure ($\pi$):** $\pi = i \cdot CRT$ - **Van't Hoff Factor ($i$):** Accounts for association or dissociation of solute. $i = \frac{Normal\ Molar\ Mass}{Observed\ Molar\ Mass}$ #### Solid State - **Types of Solids:** Crystalline (ionic, metallic, covalent, molecular) and Amorphous. - **Unit Cells:** Simple Cubic (SC), Body-Centered Cubic (BCC), Face-Centered Cubic (FCC). - **Number of Atoms per Unit Cell:** - SC: 1 - BCC: 2 - FCC: 4 - **Coordination Number:** Number of nearest neighbors. - SC: 6 - BCC: 8 - FCC: 12 - **Packing Efficiency:** - SC: 52.4% - BCC: 68% - FCC (HCP): 74% - **Density of Unit Cell:** $\rho = \frac{Z \cdot M}{a^3 \cdot N_A}$ - **Crystal Defects:** Stoichiometric (Schottky, Frenkel), Non-stoichiometric (metal excess, metal deficiency), Impurity. - **Band Theory of Solids:** Conductors, Semiconductors, Insulators. - n-type semiconductor (doping with group 15 element) - p-type semiconductor (doping with group 13 element) ### Environmental Chemistry - **Pollutants:** Classification (primary, secondary, biodegradable, non-biodegradable). - **Air Pollution:** Tropospheric (smog, acid rain, greenhouse effect) and Stratospheric (ozone depletion). - **Water Pollution:** BOD, COD, Eutrophication. - **Soil Pollution:** Pesticides, industrial wastes. - **Green Chemistry:** Principles to reduce environmental impact.