Formic acid

Some ants make a special liquid.

This liquid helps them stay safe. They can spray it to defend their homes.

You can find this liquid in many plants. It is in stinging nettles. It is also in some fruits. You can find it in apples and kiwis.

It is also in some vegetables. Onions have a lot of it. Eggplants and cucumbers have a little bit.

People use this liquid for many jobs. It helps keep animal food fresh. It can even help make leather.

Nature is full of tiny wonders!

Formic acid is a simple liquid. It has a very strong smell.

You can find it in nature. Many ants make it. They spray it to defend their nests. Some caterpillars spray it too. It is also in stinging nettle plants. You can find it in many fruits. Apples and kiwis have it. Onions have a lot of it. Eggplants and cucumbers have a little bit.

People use formic acid for many jobs. It is used to make leather. It is also used to dye cloth. In farming, it helps keep animal food fresh. It can stop bad germs in feed. This helps the food stay good for a long time.

Scientists also study it for energy. It might help store hydrogen. This could be used for fuel cells. In the past, people learned about it from ants. A man named John Ray described it in 1671. Today, factories make it from carbon monoxide. This is a gas used in many chemical steps.

Formic acid is a very simple liquid. It is known as the simplest carboxylic acid. This means it belongs to a group of organic acids. It has a very strong and sharp smell. This scent can be felt deep in the nose.

This acid is very useful in many different ways. It helps scientists build new things in labs. It also appears naturally in many parts of our world.

Nature makes this acid in many surprising places. Most ants produce it to defend their homes. Some wood ants even spray it at their prey. The puss moth caterpillar sprays it when it feels threatened. You can also find it in stinging nettle plants. It is even inside many foods we eat. For example, onions have 45 mg per 100 g. Apples have 2 mg per 100 g. Kiwi fruit has 1 mg per 100 g. Even cucumbers have a tiny amount of 0.11 mg.

People have studied this acid for a long time. In the 15th century, some people noticed ant hills smelled acidic. In 1671, a naturalist named John Ray described how to get it. He did this by distilling many ants. Later, a French chemist named Joseph Gay-Lussac made it in a lab. He used hydrocyanic acid to do this. In 1855, another French chemist named Marcellin Berthelot found a new way. He used carbon monoxide to make it. This is similar to how we make it today.

Today, factories produce huge amounts of formic acid. Much of it is made from carbon monoxide. In 2009, production was split between Europe and Asia. Germany and China are major producers. Big companies like BASF and Eastman Chemical Company make it. It is used for many important jobs. About 30% of it is used for animal feed in 2009. It helps keep food fresh for farm animals. It also stops bad bacteria from growing in the feed.

Formic acid can also help us with energy. Scientists think it might help store hydrogen. It can hold much more hydrogen than compressed gas. This could be very helpful for fuel cells.

It is also used to make leather. About 23% of the world's supply goes to tanning leather. It is used to dye and finish cloth too. It even helps in science tools like chromatography. This helps scientists separate tiny parts of a sample. It is a small molecule with a very big impact.

Formic acid is a simple organic compound known as the simplest carboxylic acid. It has the chemical formula HCOOH and a molecular structure that makes it very reactive. This colorless liquid has a pungent and penetrating odor that can be felt deep in the nose. Because it is a strong acid, it plays many roles in both nature and industry. It serves as a vital intermediate in chemical synthesis, which is the process of building complex molecules. In the natural world, it acts as a defense tool for various insects and plants.

The chemical behavior of formic acid is defined by its unique structure. In its liquid state, it can undergo a process called supercooling, where it stays liquid below its freezing point. When it is in a gas phase or in certain hydrocarbons, the molecules do not stay separate. Instead, they form hydrogen-bonded dimers, which are pairs of molecules held together by hydrogen bonds.

This tendency to bond with itself means that gaseous formic acid does not follow the ideal gas law. In its solid form, the molecules create an endless network of these hydrogen bonds.

Formic acid is found in many different biological sources. Most ant species produce it to defend their nests or to attack prey. For example, wood ants from the genus Formica can spray the acid. The puss moth caterpillar also sprays it when it feels threatened by predators. Plants like the stinging nettle contain the acid in tiny hairs called trichomes. It is also present in many foods in small amounts. Onions contain 45 mg per 100 g, while apples contain 2 mg per 100 g. Kiwi fruit has 1 mg per 100 g, and cucumbers have a very low concentration of 0.11 mg per 100 g.

Humans have been aware of this substance for centuries. As early as the 15th century, alchemists noticed that ant hills released acidic vapors. In 1671, the English naturalist John Ray was the first to describe how to isolate the acid. He did this by distilling large numbers of ants. Later, the French chemist Joseph Gay-Lussac first synthesized the acid from hydrocyanic acid. In 1855, another French chemist, Marcellin Berthelot, developed a method using carbon monoxide. This carbon monoxide method is very similar to how the acid is produced in modern industry.

Modern industrial production relies on several chemical pathways. One common method involves reacting methanol and carbon monoxide to create methyl formate. This reaction requires a strong base, such as sodium methoxide, and is performed at 80 °C and 40 atm of pressure. The methyl formate is then hydrolyzed with water to produce formic acid. Another method involves the oxidation of biomass, such as wood or waste paper. Using a specific catalyst, scientists can convert these materials into formic acid and carbon dioxide. In 2009, global production was split mostly between Europe and Asia. Germany and China are the primary leaders in manufacturing this chemical.

Formic acid has many important uses in agriculture and manufacturing. About 30% of the global consumption in 2009 was used for livestock feed. It acts as a preservative and an antibacterial agent to keep feed nutritious. In Europe, it is used on silage to help the fermentation of lactic acid. It also helps kill harmful bacteria like E. coli in poultry feed. Another major use is in the leather industry. In 2009, tanning accounted for 23% of global consumption. It is also used to dye and finish textiles, which uses about 9% of the supply.

Scientists also look to formic acid for future energy solutions. It can be used in fuel cells to provide power. One interesting possibility is using it for hydrogen storage. Formic acid contains 53 g/L of hydrogen at room temperature. This is three and a half times more hydrogen than can be held in compressed gas at 350 bar. This high density makes it a very interesting subject for energy research. Additionally, it is used in laboratory settings for chromatography. This helps scientists separate complex structures like proteins and viruses during analysis.