Acetic Acid is written CH₃COOH. With school atomic masses the molar mass is 60 g/mol. Acetic acid is a weak carboxylic acid and the acid component of vinegar.
H₂O
WaterNH₃
AmmoniaCO₂
Carbon DioxideH₂O₂
Hydrogen PeroxideSO₂
Sulfur DioxideNO₂
Nitrogen DioxideHCl
Hydrochloric AcidH₂SO₄
Sulfuric AcidHNO₃
Nitric AcidCH₄
MethaneC₂H₆
EthaneC₃H₈
PropaneC₄H₁₀
ButaneC₂H₄
EthyleneC₂H₂
AcetyleneC₆H₆
BenzeneC₇H₈
TolueneC₁₀H₈
NaphthaleneC₆H₁₂
CyclohexaneCH₃OH
MethanolC₂H₅OH
EthanolCH₃COOH
Acetic AcidHCHO
FormaldehydeCH₃COCH₃
AcetoneC₄H₁₀O
Diethyl EtherC₂H₇N
EthylamineC₂H₅NO
AcetamideC₆H₁₂O₆
GlucoseC₆H₁₂O₆
FructoseC₁₂H₂₂O₁₁
SucroseCO(NH₂)₂
UreaC₂₇H₄₆O
CholesterolC₉H₈O₄
AspirinC₈H₉NO₂
AcetaminophenC₁₃H₁₈O₂
IbuprofenC₈H₁₀N₄O₂
CaffeineC₆H₆N₂O
NicotinamideC₆H₈O₆
Ascorbic AcidC₁₆H₁₈N₂O₄S
Penicillin GC₂H₆O₂
Ethylene GlycolC₈H₈
StyreneC₂H₃Cl
Vinyl ChlorideC₃H₅NO
AcrylamideC₆H₁₁NO
CaprolactamLiCl
Lithium chlorideNa₂O
Sodium oxideNaCl
Sodium chlorideMgF₂
Magnesium fluorideAlCl₃
Aluminum chlorideCaO
Calcium oxideCaC₂
Calcium carbideKNO₃
Potassium nitrateMg₃(PO₄)₂
Magnesium phosphateAl₂(SO₄)₃
Aluminum sulfateMg(OH)₂
Magnesium hydroxideNH₄Cl
Ammonium chlorideNH₄OH
Ammonium hydroxideCuO
Copper(II) oxideCu₂O
Copper(I) oxideFeSO₄
Iron(II) sulfateFe₂(SO₄)₃
Iron(III) sulfatePbCO₃
Lead(II) carbonateMgO
Magnesium oxideAl₂S₃
Aluminum sulfideLiF
Lithium fluoride(NH₄)₂S
Ammonium sulfideKF
Potassium fluorideNiCl₂
Nickel(II) chlorideKCN
Potassium cyanideCH₃COONa
Sodium acetateCaCO₃
Calcium carbonateNa₃P
Sodium phosphideBeBr₂
Beryllium bromideFeO
Iron(II) oxideHg₂Cl₂
Mercury(I) chlorideHg(NO₃)₂
Mercury(II) nitrateCH₃COOCu
Copper(I) acetateSiO₂
Silicon dioxideP₄O₁₀
Tetraphosphorus decaoxideN₂O₅
Dinitrogen pentoxideCO
Carbon monoxideHF
Hydrogen fluoridePCl₅
Phosphorus pentachlorideCF₄
Carbon tetrafluorideSF₆
Sulfur hexafluorideNBr₃
Nitrogen tribromideN₂O
Dinitrogen monoxideN₂O₃
Dinitrogen trioxideCS₂
Carbon disulfideCl₂O₇
Dichlorine heptoxideBF₃
Boron trifluorideCCl₄
Carbon tetrachlorideSO₃
Sulfur trioxideSiCl₄
Silicon tetrachlorideP₂S₅
Diphosphorus pentasulfideBCl₃
Boron trichloridePBr₃
Phosphorus tribromideCBr₄
Carbon tetrabromideNF₃
Nitrogen trifluorideOF₂
Oxygen difluorideNCl₃
Nitrogen trichlorideH₂S
Hydrogen sulfidePH₃
PhosphineBeCl₂
Beryllium chlorideHCN
Hydrogen cyanideClF₃
Chlorine trifluorideXeF₂
Xenon difluorideAcetic acid is a weak carboxylic acid and the acid component of vinegar. Its conjugate base acetate is central to many biochemical pathways.
Properties
Molar mass
60.052 g/mol
Boiling point
117.9 °C
pKa
4.76
Melting point
16.6 °C
Density
1.049 g/cm³
Uses
Food acidulant and vinegar · Vinyl acetate and acetate ester synthesis · Buffer preparation in labs
Exam note
Systematic name
Ethanoic acid
Compound class
It is a weak carboxylic acid and the acid in vinegar.
Formula unit
The molecule is covalent. Its reactivity comes from the –COOH carboxyl group.
Aqueous solution
It ionizes partly in water as a weak acid. Its pKa is 4.76. The conjugate base is the acetate ion, CH₃COO⁻.
Watch the formula
The molecular formula is C₂H₄O₂ and the empirical formula is CH₂O. Vinegar is not pure acetic acid; it is about a 5–8% aqueous solution. The salt from the carbonate reaction is sodium acetate.
Sample reaction
CH₃COOH + NaHCO₃ → CH₃COONa + H₂O + CO₂
Vinegar and baking soda react in an acid-base reaction. The fizz is carbon dioxide gas.
Molar mass calculation
Masses given in the question come first. When none are given, school values put the total at 60 g/mol.
+
+
= 60 g/mol
CH₃COOH
C₂H₄O₂
CH₂O
The empirical formula is CH₂O. The molecular formula is a whole-number multiple of that ratio.
Open in the molar mass calculatorThe same count with periodic-table atomic masses gives 60.052 g/mol.
| Element | Atom count | Contribution (g/mol) | Mass % |
|---|---|---|---|
| Carbon (C) | 2 | 24.022 | 40.0 |
| Hydrogen (H) | 4 | 4.032 | 6.7 |
| Oxygen (O) | 2 | 31.998 | 53.3 |
| Total | 60.052 | 100 |
Common questions
What is acetic Acid?
Acetic acid is a weak carboxylic acid and the acid component of vinegar. Its conjugate base acetate is central to many biochemical pathways.
What is the formula of acetic Acid?
Acetic Acid is written CH₃COOH. The molecular formula is C₂H₄O₂. The empirical formula is CH₂O. The systematic name is Ethanoic acid. The molecule is covalent. Its reactivity comes from the –COOH carboxyl group.
What is the molar mass of acetic Acid?
Acetic Acid has a molar mass of 60.052 g/mol from the atomic masses on the periodic table. With school atomic masses the total is 60 g/mol, counting 2 carbon, 4 hydrogen and 2 oxygen.
How does acetic Acid behave in water?
It ionizes partly in water as a weak acid. Its pKa is 4.76. The conjugate base is the acetate ion, CH₃COO⁻.
What is a sample reaction for acetic Acid?
Vinegar and baking soda react in an acid-base reaction. The fizz is carbon dioxide gas. CH₃COOH + NaHCO₃ → CH₃COONa + H₂O + CO₂
What is acetic Acid used for?
Acetic Acid is used for food acidulant and vinegar, vinyl acetate and acetate ester synthesis and buffer preparation in labs.
What should you watch for with acetic Acid on an exam?
The molecular formula is C₂H₄O₂ and the empirical formula is CH₂O. Vinegar is not pure acetic acid; it is about a 5–8% aqueous solution. The salt from the carbonate reaction is sodium acetate.