Formic Acid: Formula, Uses & Production

Important facts about formic acid

Fig. 1: Structural formula of formic acid

• will also be formic acid or formylic acid called

• Latin: acidum formicum from formica»Ant»

• is a clear liquid

• has a strong pungent odor

• is the simplest carboxylic acid and shortest chain alkanoic acid

• can also as aldehyde react

• the empirical formula is (see structural formula)

• 1670 was this acid in wood ants discovered

Properties of formic acid

• Molecular formula: CH₂O₂

• molar mass: 46.0 g/mol

• Melting point: 8°C

• Boiling point: 100.7°C

• Volatility: slightly volatile

• Solubility: soluble in water in any ratio due to the polar carboxyl group

• Acid constant: pKa value = 3.75

Structure of formic acid

Fig. 2: Structural formula of formic acid with marking of the carboxylic acid group. Source:

Formic acid has one in the molecule carboxyl groupso one – COOH – group. This makes it possible that between the molecules hydrogen bonds form. These in turn explain the high boiling and melting point of formic acid. So have the boiling or melting process additional thermal energy to be added to the break hydrogen bonds.

Other substances such as propane have against no hydrogen bonds, so too no high boiling or melting temperatures.

Production of formic acid

Originally was formic acid really of ants won. In the year 1671 distilled the British naturalist John Ray (1627 – 1705) ants and obtained its acid from it. This is where the term «formic acid» comes from.

today but you only ask them synthetic after the from Marcellin Berthelot 1855 invented procedures. So no more insects have to die for it.

The synthesis is divided into two process stepsat them toxic carbon monoxide is used:

1.) Sodium Hydroxide reacts with carbon monoxide to sodium formate

2.) sodium formate reacts in a neutralization reaction With sulfuric acid to formic acid and sodium sulfate

1.) methanol reacts with carbon monoxide to ethyl formate

2.) ethyl formate reacts with water to formic acid and methanol

The methanol that is recovered at the end can be used as a starting product for the synthesis.

For example, formic acid was no longer only obtained as a by-product, but deliberately synthetically produced.

Use of formic acid

What animals and plants to self defense can also use the people before Illness protection.

Find out now the areas of application of formic acid in the animal and plant world, as well as how we humans use the toxic acid.

Occurrence of formic acid in nature

Fig. 3: Stinging hair of a nettle, source: seilnacht.com

In nature, some living things use formic acid too defense purposes. Ants in particular use their acid for defense from predators. The acid accounts for up to 50% of the insect’s body weight.

But not only ants use formic acid to defend themselves from enemies or to fight them – it is widespread in nature. For example scorpions and jellyfish use their caustic powers, as do some Plant. The best known is probably the nettle. Their stinging hairs are filled with nettle poisonamong other things formic acid contains.

Human use of formic acid

Formic acid not only has a useful function for the plant world, but also for us people have the special feature this acid discovered:

Formic acid for beekeepers:

Beekeepers use them antibacterial Effect of formic acid, for example Varroa mites to fight. Due to the fact that the mites the weaken bees and even kill they are partly responsible for the enormous bee deaths. In addition, already infested bees less honey produce and are less efficient. Thus, formic acid provides an effective antidote for it.

Formic acid in the textile and leather industry:

In the textile and leather industry, formic acid is used to stain, impregnate and matt leather and many other textiles.

Formic acid in medicine:

Methanoic acid is used medicinally because of its anti-inflammatory properties antirheumatic drug used. Also against warts it is used. Formic acid is also said to promote blood circulation. Therefore she also becomes external treatment used by muscle and joint complaints – but only sufficiently dilutedotherwise the acid can cause skin irritation and chemical burns.

In private households, formic acid is often used as a descale from washing machines used.

Concentrated formic acid can also be used to clean raw gemstones be used as they limestone and other contaminants and thus cleanses the gemstone without damaging it. However, this method of cleaning should only be used with acid resistant gemstones are applied.

salts of formic acid

are typical of acids salt formation reactions. Methanoic acid also forms salts formates to be named. For example iron, zinc, magnesium and other base metals dissolve with evolution of hydrogen. The salts of formic acid, the formates (according to IUPAC methanoates).

With magnesium arises magnesium formatewith copper forms copper formate and with sodium forms sodium formate. This always produces hydrogen or water as byproduct.

A few to understand Reaction Equation Examples:

Magnesium and formic acid react to form magnesium formate and hydrogen

Copper oxide and formic acid react to form copper formate and water

Sodium hydroxide and formic acid react to form sodium formate and water

Dangers of formic acid

Fig. 4: Formic acid in a bottle with a vent valve, source: seilnacht.com

Do you come into contact with formic acid or its concentrated steaming It comes to irritation of the airways and eyes and can lead to shortness of breath. On the skin, concentrations of 10% and above cause severe irritation acid burns and Blow.

At the breathe in the mucous membranes are irritated, blisters can also form in the mouth and throat. In addition chemical burns can occur with prolonged exposure fatal damage in the liver, kidneys or heart.

Because of these many dangers, using formic acid is also necessary specially stored will:

Pure formic acid in the laboratory must be in a container with vent valvesuch as cool be stored, because when it decays, Carbon monoxide respiratory poison arises. In addition, the container must have a pressure equalization allow as it is due to the carbon monoxide to a overpressure inside the container and there is a risk that it will eventually burst.

The most important facts about formic acid at a glance!

• Formic acid was originally made from wood ants won, but today it mainly becomes synthetic manufactured

• Methanoic acid is the simplest carboxylic acid and shortest chain alkanoic acid

• In the Flora and fauna comes to formic acid defense purposes deployed in front of enemies

• Methanoic acid is considered a classic stimulants and mood enhancers in the homeopathy

• forms formic acid salts, the formates to be named

• Formic acid and its fumes can lead to Irritations, burns, blisters and fatal damage lead to the organs