Glossary — 25 Key Terms — Notes

#	Term	Definition
1	Carboxylic acid	Organic compound with –COOH group; general formula RCOOH
2	Carboxylate ion	RCOO–, the conjugate base of a carboxylic acid; resonance-stabilized
3	pKa	Negative log of Ka; lower pKa = stronger acid
4	Ka	Acid dissociation constant; Ka = [RCOO–][H+]/[RCOOH]
5	Resonance stabilization	Delocalization of electrons over multiple bonds/atoms, lowering energy
6	Bond order	Average number of bonds between two atoms; 1.5 in carboxylate C–O bonds
7	Inductive effect (–I)	Electron withdrawal through sigma bonds by electronegative groups
8	+I effect	Electron donation through sigma bonds by alkyl groups
9	Alpha-carbon	Carbon adjacent to the functional group (–COOH here); C-2 in IUPAC
10	Alpha-hydrogen	Hydrogen on the alpha-carbon; required for HVZ reaction
11	HVZ reaction	Hell-Volhard-Zelinsky: alpha-halogenation of RCOOH using X2/Red P
12	Fischer esterification	Acid-catalyzed reversible condensation of RCOOH + R'OH → RCOOR' + H2O
13	Saponification	Base-catalyzed irreversible hydrolysis of ester: RCOOR' + NaOH → RCOONa + R'OH
14	Decarboxylation	Loss of CO2 (–COOH group) from a carboxylic acid salt; soda lime method
15	Soda lime	NaOH + CaO mixture; used for decarboxylation of carboxylate salts
16	LiAlH4	Lithium aluminium hydride; strong reducing agent; reduces RCOOH → RCH2OH
17	NaBH4	Sodium borohydride; mild reducing agent; does NOT reduce RCOOH
18	SOCl2	Thionyl chloride; converts RCOOH → RCOCl + SO2 + HCl
19	Acyl chloride	RCOCl; highly reactive acylating agent; more reactive than RCOOH
20	PCl5	Phosphorus pentachloride; converts RCOOH → RCOCl + POCl3 + HCl
21	Kolbe electrolysis	Electrochemical oxidation of RCOO– at anode → R–R + 2CO2
22	Grignard carboxylation	RMgX + CO2 → RCOOMgX → RCOOH; adds –COOH group (one carbon)
23	Nitrile hydrolysis	RCN + H3O+ → RCOOH + NH4+; acid hydrolysis of nitriles
24	Acidity ladder	pKa hierarchy: RCOOH (4–5) > ArOH (10) > H2O (15.7) > ROH (16–18) > RC≡CH (25)
25	Walden inversion	SN2 inversion of configuration at alpha-carbon when alpha-halo acid reacts with nucleophile