Ionization Constants of Weak Acids, Front matter | Chemistry 2e

Learning objectives

Ionization Constants of Weak Acids
Acid	Formula	K_a at 25 °C	Lewis Structure
acetic	CH₃CO₂H	1.8 $\times$ 10⁻⁵	View original figure (external; image not reproduced in this text edition) Original figure description: Lewis structure of acetic acid, an organic compound found in vinegar. It illustrates the arrangement of atoms, bonds, and lone pairs in the molecule.
arsenic	H₃AsO₄	5.5 $\times$ 10⁻³	View original figure (external; image not reproduced in this text edition) Original figure description: Lewis structure of arsenic acid (H3AsO4) showing the central arsenic atom bonded to one oxygen with a double bond and three hydroxyl groups, with lone pairs on oxygen atoms.
	View original figure (external; image not reproduced in this text edition) Original figure description: The chemical formula for dihydrogen arsenate, H2AsO4-, is displayed on a white background. The 'H2' is in a reddish-brown color, while 'AsO4-' is black.	1.7 $\times$ 10⁻⁷
	View original figure (external; image not reproduced in this text edition) Original figure description: The chemical formula for hydrogen arsenate, HAsO4^2-.	3.0 $\times$ 10⁻¹²
arsenous	H₃AsO₃	5.1 $\times$ 10⁻¹⁰	View original figure (external; image not reproduced in this text edition) Original figure description: A chemical diagram illustrates the Lewis structure of arsenous acid (H3AsO3), featuring a central arsenic atom single-bonded to three oxygen atoms, each further bonded to a hydrogen atom, and lone pairs on the oxygen atoms.
boric	H₃BO₃	5.4 $\times$ 10⁻¹⁰	View original figure (external; image not reproduced in this text edition) Original figure description: A chemical structure diagram of boric acid, showing a central boron atom bonded to three hydroxyl groups (B(OH)3).
carbonic	H₂CO₃	4.3 $\times$ 10⁻⁷	View original figure (external; image not reproduced in this text edition) Original figure description: Lewis structure of carbonic acid (H2CO3), showing its covalent bonds and lone pair electrons.
carbonic	View original figure (external; image not reproduced in this text edition) Original figure description: The bicarbonate ion (HCO3-) plays a crucial role in maintaining pH balance in the body and is an important component of the carbonic acid-bicarbonate buffer system.	4.7 $\times$ 10⁻¹¹
formic	HCO₂H	1.8 $\times$ 10⁻⁴	View original figure (external; image not reproduced in this text edition) Original figure description: Lewis structure of formic acid (HCOOH) with lone pairs shown, illustrating its molecular arrangement and bonding.
hydrazoic	HN₃	2.5 $\times$ 10⁻⁵	View original figure (external; image not reproduced in this text edition) Original figure description: Resonance structures of hydrazoic acid (HN3), depicting the delocalization of electrons and formal charges across the nitrogen atoms.
hydrocyanic	HCN	4.9 $\times$ 10⁻¹⁰
hydrofluoric	HF	6.4 $\times$ 10⁻⁴
hydrogen peroxide	H₂O₂	2.4 $\times$ 10⁻¹²	View original figure (external; image not reproduced in this text edition) Original figure description: Lewis structure of Hydrogen Peroxide (H2O2), depicting two hydrogen atoms bonded to two oxygen atoms, with each oxygen also featuring two lone pairs of electrons.
hydrogen selenide	H₂Se	1.29 $\times$ 10⁻⁴
hydrogen selenide	HSe^–	1 $\times$ 10⁻¹²
hydrogen sulfate ion	View original figure (external; image not reproduced in this text edition) Original figure description: The chemical formula for the bisulfate ion, HSO4-, is displayed.	1.2 $\times$ 10⁻²	View original figure (external; image not reproduced in this text edition) Original figure description: Lewis structure of the bisulfate ion (HSO4-), showing sulfur double-bonded to two oxygens, single-bonded to a negatively charged oxygen, and single-bonded to a hydroxyl group.
hydrogen sulfide	H₂S	8.9 $\times$ 10⁻⁸
hydrogen sulfide	HS^–	1.0 $\times$ 10⁻¹⁹
hydrogen telluride	H₂Te	2.3 $\times$ 10⁻³
hydrogen telluride	HTe^–	1.6 $\times$ 10⁻¹¹
hypobromous	HBrO	2.8 $\times$ 10⁻⁹
hypochlorous	HClO	2.9 $\times$ 10⁻⁸
isocyanic	HCNO	2 $\times$ 10⁻⁴	View original figure (external; image not reproduced in this text edition) Original figure description: A Lewis structure representation of isocyanic acid (HNCO). This molecular diagram shows a hydrogen atom bonded to a nitrogen atom, which is double-bonded to a carbon atom, which is also double-bonded to an oxygen atom. Lone pairs are present on the nitrogen and oxygen atoms.
nitrous	HNO₂	4.6 $\times$ 10⁻⁴	View original figure (external; image not reproduced in this text edition) Original figure description: The Lewis structure of nitrous acid (HNO2) displays single bonds between nitrogen and two oxygen atoms, with one oxygen bonded to a hydrogen. Lone pairs are also shown on the oxygen and nitrogen atoms.
oxalic	H₂C₂O₄	6.0 $\times$ 10⁻²	View original figure (external; image not reproduced in this text edition) Original figure description: Lewis structure of oxalic acid, showing two hydroxyl groups and two carbonyl groups. The molecule has a chemical formula of H2C2O4.
oxalic	View original figure (external; image not reproduced in this text edition) Original figure description: The image shows the chemical formula for the hydrogen oxalate ion (also known as bioxalate), represented as HC2O4-. The 'H' is in a brownish color, while 'C2O4-' is in black, with the minus sign indicating its ionic nature.	6.1 $\times$ 10⁻⁵
phosphoric	H₃PO₄	7.5 $\times$ 10⁻³	View original figure (external; image not reproduced in this text edition) Original figure description: Lewis structure of phosphoric acid (H3PO4), depicting a central phosphorus atom double-bonded to one oxygen and single-bonded to three other oxygen atoms, each of which is bonded to a hydrogen atom.
	View original figure (external; image not reproduced in this text edition) Original figure description: The chemical formula for the dihydrogen phosphate ion, H2PO4-.	6.2 $\times$ 10⁻⁸
	View original figure (external; image not reproduced in this text edition) Original figure description: The chemical formula for a hydrogen phosphate ion, represented as HPO4 with a 2- charge.	4.2 $\times$ 10⁻¹³
phosphorous	H₃PO₃	5 $\times$ 10⁻²	View original figure (external; image not reproduced in this text edition) Original figure description: Lewis structure of phosphorous acid (H3PO3), featuring a central phosphorus atom bonded to three hydroxyl groups, with each oxygen having two lone pairs.
phosphorous	View original figure (external; image not reproduced in this text edition) Original figure description: A chemical formula for dihydrogen phosphite ion, H2PO3-, is displayed on a white background. The 'H2' is in a reddish-brown color, while 'PO3-' is in black.	2.0 $\times$ 10⁻⁷
sulfurous	H₂SO₃	1.6 $\times$ 10⁻²	View original figure (external; image not reproduced in this text edition) Original figure description: Lewis structure of sulfuric acid (H2SO4), showing the central sulfur atom bonded to two hydroxyl groups and one oxygen, along with lone pairs of electrons.
sulfurous	View original figure (external; image not reproduced in this text edition) Original figure description: The chemical formula for the bisulfite ion, HSO3-, is displayed.	6.4 $\times$ 10⁻⁸

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