Formic acid name is taken from the Latin word Formica which means “ant”. It can be written as HOOCH. Let us discuss some important facts about formic acid in this article.
Formic acid is stronger than other acids. It is soluble in water. In vapor phase it form cyclic dimer which is joined by hydrogen bond. An ant is a natural source of formic acid.
In industry, methanol is used for producing formic acid. Let us go through various properties of formic acid like IUPAC name, Chemical formula, CAS number, and more such parameters in the following editorial.
Formic acid IUPAC name
IUPAC’s name of formic acid is Methanoic acid. It is also known as formylic acid. As a single carbon atom is present, it is systematically named methanoic acid.
Formic acid chemical formula
The formic acid chemical formula is HCOOH. As written in the formula, it contains a single carboxylic group.
Formic acid CAS number
CAS number of formic acid is predicted as 64-18-6.
Formic acid Chem Spider ID
ChemSpider ID for formic acid is 109712.
Formic acid chemical classification
- Formic acid contains a carboxyl group (-COOH), which comes under the carboxylic acid group.
- Formic acid chemical classification is done depending on the structure of a compound.
- The structure of formic acid is given below.
Formic acid molar mass
The molar mass of Formic acid is predicted as 46.03g/mol.
Molar mass = C (12.0107) +2*H (2*1.00784) +2*O (2*15.999) = 46.09 g/mole
Formic acid color
Formic acid is observed as a colorless fuming liquid.
Formic acid viscosity
Formic acid shows different values of viscosity at different temperatures. It will be clear below.
| Temperature | Viscosity |
|---|---|
| 100C | 2.2469 |
| 200C | 1.7844 |
| 400C | 1.2190 |
| 1000C | 0.5492 |
Formic acid molar density
Molar density in 95% (W/W) formic acid is 1.22g/ml at 250C. It indicates the weight of 1 ml of formic acid is 1.22 grams at 250C.
Formic acid melting point
The melting point of formic acid is 8.40C.
Formic acid boiling point
The boiling point of formic acid is 100.80C
Formic acid state at room temperature
Formic acid is found in liquid at room temperature.
Formic acid covalent bond
Formic acid contains carbon atom, which forms all covalent bond. In formic acid, between carbon and hydrogen atoms single bond is present, between carbon and oxygen double bond is present, and in the carbon and hydroxyl group a single bond is present.
Formic acid electron configurations
An electron is arranged around the nucleus in an orbital this is called electron configuration. There are four types of orbitals s,p,d, and f. Let us see the electronic configuration of formic acid.
The electron configuration of the carbon, hydrogen, and oxygen atoms in formic acid is below.
- Carbon – 1s2 2s2 2p2
- Hydrogen – 1s2
- Oxygen – 1s2 2s2 2p4
The formic acid oxidation state
The oxidation state in the case of formic acid is observed as +2.
Formic acid acidity/alkaline
As the name indicates, formic acid is acidic. The acidity value (pKa) of formic acid is 3.75. But it is a weak acid, partially dissociating in an aqueous solution.
Is formic acid odorless?
Formic acid shows a pungent, penetrating odor.
Is formic acid paramagnetic?
The presence of unpaired electrons indicates paramagnetic properties, whereas paired electrons indicates diamagnetism. Let us predict formic acid is paramagnetic or diamagnetic.
Formic acid shows a diamagnetic property. Formic acid contains 18 electrons in the valence shell.
Valence electron = 4 (C) + 1*2 (H) +6*2 (O)= 18 electron
Formic acid hydrates
Formic acid reacts with water to give trihydrate HC(OH3), which is acidic.
Formic acid crystal structure
The crystal structure of formic acid is predicted as orthorhombic. The single-crystal X-ray diffraction technique determines the crystal structure of formic acid.
Formic acid polarity and conductivity
- The polarity of formic acid is 6.0.
- Formic acid is polar as at one end oxygen has a negative charge and at the other end, carbon has a positive charge.
- In water, formic acid dissociates into two ions one is H+ and the other is COOH-.These ions conduct electricity.
- Formic acid is weak acid so a small amount of ions is formed.
- The below structure shows the polarity of formic acid.
Formic acid reaction with acid
When reacted with concentrated sulphuric acid (H2SO4), formic acid gives the product of water and carbon monoxide. This reaction is called a Dehydration reaction.
HCO2H ⟶ H2O + CO
Formic acid reaction with base
Ammonia is a weak base. When formic acid reacts with ammonia it gives ammonium formate, a salt. Here, an exchange of hydrogen ions takes place from acid to base.
- HCOOH ⟶ HCOO– + H+
- NH3 + H+ ⟶ NH4+
- HCOOH + NH3 ⟶ HCOONH4
Formic acid reaction with oxide
Formic acid reduces Ag2O to metallic silver. Formic acid reduces Fehling solution to cuprous oxide, a red colour precipitate.
- HCOOH + Ag2O ⟶ 2Ag +Co2 +H2O
- HCOOH + 2CuO ⟶ Cu2O + H2O + Co2
Formic acid reaction with metal
Formic acid reacts with metal like sodium to give sodium formate, a salt. In this reaction, hydrogen gas evolved. Formic acid undergoes decomposition on the surface of a transition metal such as Ag, Cu, Pd, Pt, and Rh. It results in dehydrogenation.
- 2HCOOH + 2Na ⟶ HCOONa + H2↑
- HCOOH ⟶ Co2 + H2 ↑
Conclusion
Formic acid has antibacterial properties, so used in the agriculture industry. As it prevents crops from an attack by pests, it is used as a pesticide. It is used in the leather and rubber manufacturing process.
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Hello everyone I am Arti D. Gokhale. My master’s with a specialization in Organic Chemistry and I graduated with Chemistry, Biology, and Zoology. I have 3 years of work experience in water analysis at the National Environmental Engineering Research Institute Nagpur.