Perchloric acid	HClO4	Large	Perchlorate ion	ClO4-	Very small
Sulfuric acid	H2SO4	Large	Hydrogen sulfate ion	HSO4-	Very small
Selenic acid	H2SeO4	Large	Hydrogen selenate ion	HSeO4-	Very small
Hydrochloric acid	HCl	Large	Chloride ion	Cl-	Very small
Hydrobromic acid	HBr	Large	Bromide ion	Br-	Very small
Hydoiodic acid	HI	Large	Iodide ion	I-	very small
Nitric acid	HNO3	~20	Nitrate ion	NO3-	~5x10-16
Hydronium ion	H3O+	1.0	Water	H2O	1.0x10-14
Oxalic acid	H2C2O4	5.9x10-1	Hydrogen oxalate ion	HC2O4-	1.7x10-14
Sulfurous acid	H2SO3	1.2x10-2	Hydrogen sulfite ion	HSO3-	8.3x10-13
Hydrogen sulfate ion	HSO4-	1.2x10-2	Sulfate ion	SO42-	8.3x10-13
Hydrogen selenate ion	HSeO4-	1.2x10-2	selante ion	SeO42-	8.3x10-13
Phosphorous acid	H3PO3	1.6x10-2	dihydrogen phosphite ion	H2PO3-	6.3x10-13
Phosphoric acid	H3PO4	7.5x10-3	Dihydrogen phosphate ion	H2PO4-	1.3x10-12
Citric acid	H3C6H5O7	7.4x10-3	Dihydrogen citrate ion	H2C6H5O7-	1.4x10-12
Hexaaquairon(III) ion	Fe(H2O)63+	6.3x10-3	Pentaaquahydroxoiron(III) ion	Fe(H2O)5OH2+	1.6x10-12
Selenous acid	H2SeO3	2.7x10-3	Hydrogen selenite ion	HSeO3-	3.7x10-12
Tellurous acid	H2TeO3	2x10-3	Hydrogen tellurite ion	HTeO3-	5x10-12
Hydrofluoric acid	HF	7.2x10-4	Fluoride ion	F-	1.4x10-11
Nitrous acid	HNO2	4.5x10-4	Nitrite ion	NO2-	2.2x10-11
Cyanic acid	HOCN	3.5x10-4	Cyanate ion	OCN-	2.9x10-11
Acetylsalicylic acid	HC9H7O4	3.0X10-4	Acetlysalicylate ion	C9H7O4-	3.3x10-11
Arsenic acid	H3AsO4	2.5x10-4	Dihydrogen arsenate ion	H2AsO4-	4.0x10-11
Formic acid	HCOOH	1.8x10-4	Formate ion	HCOO-	5.6x10-11
Lactic acid	HC3H5O3	1.4x10-4	Lactate ion	C3H5O3-	7.1X10-11
Hydrogen oxalate ion	HC2O4-	6.4x10-5	Oxalate ion	C2O42-	1.6x10-10
Benzoic acid	C6H5COOH	6.3x10-5	Benzoate ion	C6H5COO-	1.6x10-10
Anilinium ion	C6H5NH3+	2.4x10-5	Aniline	C6H5NH2	4.2x10-10
Hydrazoic acid	HN3	1.9x10-5	Azide ion	N3-	5.3x10-10
Acetic acid	CH3COOH	1.8x10-5	Acetate ion	CH3COO-	5.6x10-10
Dihydrogen citrate ion	H2C6H5O7-	1.7x10-5	Hydrogen citrate ion	HC6H5O72-	5.9x10-10
Propanoic acid	CH3CH2COOH	1.4x10-5	Propanoate ion	CH3CH2COO-	7.1x10-10
Hexaaquaaluminum ion	Al(H2O)63+	7.9x10-6	Pentaaquahydroxoaluminum ion	Al(H2O)5OH2+	1.3x10-9
Pydridinium ion	C5H5NH+	6.7x10-6	Pyridine	C5H5N	1.5x10-9
Hydroxylammonium ion	NH3OH+	1.5x10-6	Hydroxylamine	NH2OH	6.6x10-9
Dihydrogen phosphite ion	H2PO3-	7.0x10-7	Hydrogen phosphite ion	HPO32-	1.4x10-8
Carbonic acid	H2CO3	4.2x10-7	Hydrogen carbonate ion	HCO3-	2.4x10-8
Hydrogen citrate ion	HC6H5O72-	4.0x10-7	Citrate ion	C6H5O73-	2.5x10-8
Ethylenediammonium(2+) ion	H3NCH2CH2NH32+	3.7x10-7	Ethylenediammonium(1+) ion	H2NCH2CH2NH32+	2.7x10-8
Hydrogen selenite ion	HSeO3-	2.5x10-7	selenite ion	SeO32-	4.0x10-8
Hexaaquacopper(II) ion	Cu(H2O)62+	1.6x10-7	Pentaaquahydroxocopper(II) ion	Cu(H2O)5OH+	6.25x10-8
Hydrogen sulfide	H2S	1x10-7	Hydrogen sulfide ion	HS-	1x10-7
Dihydrogen phosphate ion	H2PO4-	6.2x10-8	Hydrogen phosphate ion	HPO42-	1.6x10-7
Hydrogen sulfite ion	HSO3-	6.3x10-8	Sulfite ion	SO32-	1.6x10-7
Dihydrogen arsenate ion	H2AsO4-	5.6x10-8	Hydrogen arsenate ion	HAsO42-	1.8x10-7
Hypochlorous acid	HOCl	3.5x10-8	Hypochlorite ion	OCl-	2.9x10-7
Hexaaqualead(II) ion	Pb(H2O)62+	1.5x10-8	Pentaaquahydroxolead(II) ion	Pb(H2O)5OH+	6.7x10-7
Hydrazinium ion	N2H5+	1.2x10-8	Hydrazine	N2H4	8.5x10-7
Hydrogen tellurite ion	HTeO3-	1x10-8	Tellurite ion	TeO32-	1x10-6
Nicotinium ion	C10H14N2H+	1.0x10-8	Nicotine	C10H14N2	1.0x10-6
Morphinium ion	H2C17H18NO3+	6.2x10-9	Morphine	HC17H18NO3	1.6x10-6
Hypobromous acid	HOBr	2.5x10-9	Hypobromite ion	OBr-	4.0x10-6
Hexaaquacobalt(II) ion	Co(H2O)62+	1.3x10-9	Pentaaquahydroxocobalt(II) ion	Co(H2O)5OH+	7.7x10-6
Boric acid	B(OH)3(H2O)	7.3x10-10	Tetrahydroxoborate ion	B(OH)4-	1.4x10-5
Arsenous acid	H3AsO3	6.0x10-10	Dihydrogen arsenite ion	H2AsO3-	1.7x10-5
Ammonium ion	NH4+	5.6x10-10	Ammonia	NH3	1.8x10-5
Hydrocyanic acid	HCN	4.0x10-10	Cyanide ion	CN-	2.5x10-5
Hexaaquairon(II) ion	Fe(H2O)62+	3.2x10-10	Pentaaquahydroxoiron(II) ion	Fe(H2O)5OH+	3.1x10-5
Morphine	HC17H18NO3	1.4x10-10	Morphinate ion	C17H18NO3-
Trimethylammonium ion	(CH3)3NH+	1.4x10-10	Trimethylamine	(CH3)3N	7.4x10-5
Phenol	HC6H5O	1.3x10-10	Phenoxide ion	C6H5O-	7.7x10-5
Ethylenediammonium(1+) ion	H2NCH2CH2NH3+	1.2x10-10	Ethylenediamine	H2NCH2CH2NH2	8.5x10-5
Hydrogen carbonate ion	HCO3-	4.8x10-11	Carbonate ion	CO32-	2.1x10-4
Hexaaquanickel(II) ion	Ni(H2O)62+	2.5x10-11	Pentaaquahydroxonickel(II) ion	Ni(H2O)5OH+	4.0x10-4
Methylammonium ion	CH3NH3+	2.0x10-11	Methylamine	CH3NH2	5.0x10-4
Dimethylammonium ion	(CH3)2NH2+	1.4x10-11	Dimethylamine	(CH3)2NH	7.4x10-4
Hydrogen peroxide	H2O2	2.4x10-12	Hydroperoxide ion	HO2-	4.2x10-3
Hydrogen phosphate	HPO42-	3.6x10-13	Phosphate ion	PO43-	2.8x10-2
Hydrogen arsenate ion	HAsO42-	3.0x10-13	Arsenate ion	AsO43-	3.3x10-2
Dihydrogen arsenite ion	H2AsO3-	3.0x10-14	Hydrogen arsenite ion	HAsO32-	3.3x10-1
Water	H2O	1.0x10-14	Hydroxide ion	OH-	1.0
Hydrogen sulfide ion	HS-	1x10-19	Sulfide ion	S2-	1x105
Ethanol	C2H5OH	Very small	Ethoxide ion	C2H5O-	Large
Ammonia	NH3	Very small	Amide ion	NH2-	Large
Hydrogen	H2	Very small	Hydride ion	H-	Large
Methane	CH4	Very small	Methide ion	CH3-	Large