Table 6-1: Values of pKa for Various Acids

A comprehensive vocabulary review of Table 6-1, covering various acids, their corresponding conjugate bases, and experimental or reference pKa values.

Trifluoromethanesulfonic acid

A strong acid ($\text{F}_3\text{C-SO}_3\text{H}$) with the conjugate base $\text{F}_3\text{C-SO}_3^-$ and a $pK_a$ of $-13$.

Sulfuric acid

An inorganic acid ($\text{HO-SO}_2\text{-OH}$) with the conjugate base hydrogen sulfate ($\text{HO-SO}_2\text{-O}^-$) and a $pK_a$ of $-9$.

Hydrochloric acid

A mineral acid ($\text{HCl}$) with chloride ($\text{Cl}^-$) as its conjugate base and a $pK_a$ of $-7$.

Hydronium ion

The protonated species $\text{H}_3\text{O}^+$ with water ($\text{H}_2\text{O}$) as its conjugate base and a reference $pK_a$ of $0$.

Trichloroethanoic acid (Trichloroacetic acid)

A halogenated carboxylic acid ($\text{Cl}_3\text{CCOOH}$) with conjugate base $\text{Cl}_3\text{CCOO}^-$ and a $pK_a$ of $0.77$.

Hydrofluoric acid

A haloacid ($\text{HF}$) with fluoride ($\text{F}^-$) as its conjugate base and a $pK_a$ of $3.2$.

Benzoic acid

An aromatic carboxylic acid with benzoate ($\text{C}_6\text{H}_5\text{COO}^-$) as its conjugate base and a $pK_a$ of $4.2$.

Ethanoic acid (Acetic acid)

A carboxylic acid ($\text{CH}_3\text{COOH}$) with acetate ($\text{CH}_3\text{COO}^-$) as its conjugate base and a $pK_a$ of $4.75$.

Hydrogen sulfide

A diprotic sulfur compound ($\text{H}_2\text{S}$) with hydrosulfide ($\text{HS}^-$) as its conjugate base and a $pK_a$ of $7.2$.

Ammonium ion

A positively charged polyatomic ion ($\text{NH}_4^+$) with ammonia ($\text{NH}_3$) as its conjugate base and a $pK_a$ of $9.4$.

Phenol

An aromatic alcohol ($\text{C}_6\text{H}_5\text{OH}$) with phenolate ($\text{C}_6\text{H}_5\text{O}^-$) as its conjugate base and a $pK_a$ of $10.0$.

Methylammonium ion

An alkylammonium cation ($\text{H}_3\text{C-NH}_3^+$) with methylamine ($\text{H}_3\text{C-NH}_2$) as its conjugate base and a $pK_a$ of $10.63$.

2,2,2-Trifluoroethanol

A fluorinated primary alcohol with the conjugate base $\text{CF}_3\text{CH}_2\text{O}^-$ and a $pK_a$ of $12.4$.

Water

A neutral solvent molecule ($\text{H}_2\text{O}$) with hydroxide ($\text{HO}^-$) as its conjugate base and a $pK_a$ of $14$.

2-Chloroethanol

A chlorinated alcohol with conjugate base $\text{ClCH}_2\text{CH}_2\text{O}^-$ and a $pK_a$ of $14.3$.

Methanol

The simplest alcohol ($\text{CH}_3\text{OH}$), with methoxide ($\text{CH}_3\text{O}^-$) as its conjugate base and a $pK_a$ of $15.5$.

Ethanol

A two-carbon alcohol with ethoxide as its conjugate base and a $pK_a$ of $16$.

Propan-2-ol (Isopropyl alcohol)

A secondary alcohol with isopropoxide as its conjugate base and a $pK_a$ of $16.5$.

Methylpropan-2-ol (tert-Butyl alcohol)

A tertiary alcohol with tert-butoxide as its conjugate base and a $pK_a$ of $19$.

Propanone (Acetone)

A common ketone ($\text{H}_3\text{C-CO-CH}_3$) with conjugate base $\text{H}_3\text{C-CO-CH}_2^-$ and a $pK_a$ of $20$.

Ethyne (Acetylene)

An alkyne ($\text{HC}\equiv\text{CH}$) with acetylide anion ($\text{HC}\equiv\text{C}^-$) as its conjugate base and a $pK_a$ of $25$.

Aniline (Phenylamine)

An aromatic amine ($\text{C}_6\text{H}_5\text{NH}_2$) with conjugate base $\text{C}_6\text{H}_5\text{NH}^-$ and a $pK_a$ of $27$.

Hydrogen gas

A diatomic gas ($\text{H}_2$) with hydride ($\text{H}^-$) as its conjugate base and a $pK_a$ of $35$.

Ammonia

A basic hydride ($\text{NH}_3$) with amide ion ($\text{H}_2\text{N}^-$) as its conjugate base and a $pK_a$ of $36$.

N-Methylmethanamine (Dimethylamine)

A secondary aliphatic amine with dimethylamide as its conjugate base and a $pK_a$ of $38$.

Ethene (Ethylene)

An alkene ($\text{H}_2\text{C=CH}_2$) with vinyl anion ($\text{H}_2\text{C=CH}^-$) as its conjugate base and a $pK_a$ of $44$.

Ethoxyethane (Diethyl ether)

An aliphatic ether with conjugate base formed by carbon deprotonation and a $pK_a$ of $45$.

Methane

The simplest alkane ($\text{CH}_4$), with the methyl anion ($\text{H}_3\text{C}^-$) as its conjugate base and a $pK_a$ of $48$.

Ethane

A saturated hydrocarbon ($\text{CH}_3\text{CH}_3$) with the ethyl anion ($\text{CH}_3\text{CH}_2^-$) as its conjugate base and a $pK_a$ of $50$.