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Chemistry Textbook

Appendix H

Ionization Constants of Weak Acids
Ionization Constants of Weak Acids
Ionization Constants of Weak Acids
Acid Formula Ka at 25 °C Lewis Structure
acetic CH3CO2H 1.8 ×× 10−5
arsenic H3AsO4 5.5 ×× 10−3
 1.7 ×× 10−7
 3.0 ×× 10−12
arsenous H3AsO3 5.1 ×× 10−10
boric H3BO3 5.4 ×× 10−10
carbonic H2CO3 4.3 ×× 10−7
 4.7 ×× 10−11
cyanic HCNO 2 ×× 10−4
formic HCO2H 1.8 ×× 10−4
hydrazoic HN3 2.5 ×× 10−5
hydrocyanic HCN 4.9 ×× 10−10
hydrofluoric HF 6.4 ×× 10−4
hydrogen peroxide H2O2 2.4 ×× 10−12
hydrogen selenide H2Se 1.29 ×× 10−4
HSe 1 ×× 10−12
hydrogen sulfate ion  1.2 ×× 10−2
hydrogen sulfide H2S 8.9 ×× 10−8
HS 1.0 ×× 10−19
hydrogen telluride H2Te 2.3 ×× 10−3
HTe 1.6 ×× 10−11
hypobromous HBrO 2.8 ×× 10−9
hypochlorous HClO 2.9 ×× 10−8
nitrous HNO2 4.6 ×× 10−4
oxalic H2C2O4 6.0 ×× 10−2
 6.1 ×× 10−5
phosphoric H3PO4 7.5 ×× 10−3
 6.2 ×× 10−8
 4.2 ×× 10−13
phosphorous H3PO3 5 ×× 10−2
 2.0 ×× 10−7
sulfurous H2SO3 1.6 ×× 10−2
 6.4 ×× 10−8