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Fluorine: The Most Reactive Element in Periodic Table

Errah is a bookwormy and logophilic writer and science & technology teacher. He often writes about scientific ideas, theories, and research.

A model of an atom of fluorine.

A model of an atom of fluorine.

What is Fluorine?

Fluorine is the chemical element with the symbol F and atomic number 9. Its atom is the third smallest among all elements with an atomic radius of 153 pm. It has 9 electrons that surround the nucleus of its atom — 7 in its outer shell, and 2 in its inner shell. Its atomic weight is 18.998403 and its density is 0.001696 g/cm3.

Fluorine usually exists in the form of a pale-yellow gas at room temperature. It has a strong odor and is often described as having a "pungent" smell. It condenses into a bright yellow liquid at -188.12 °C. Fluorine solidifies into soft and transparent crystals at -219.6 °C and becomes very hard and opaque at -228°C.

At room temperature, fluorine exists as yellowish gas.

At room temperature, fluorine exists as yellowish gas.

Fluorine is rare in the atmosphere and oceans but abundant in the earth's crust. It does not exist in nature as a free element. It is always found as a chemical compound readily combined with other molecules. The most common natural compounds of fluorine are fluorspar, topaz, tourmaline, apatite, and jadeite.

Applications of Flourine

Fluorine has a wide range of applications and its common use is in the production of sodium fluoride. Sodium fluoride is one of the ingredients added to toothpaste. It is beneficial for the prevention of tooth decay. Fluorine is essential in the production of aluminum, dye, ceramics, and fluorochemicals such as solvents and superplastics.

It is also used in a variety of industries, including petrochemicals, etching glass and enamel, cable insulation, smelting flux, and agricultural chemicals. Fluorine is also an important chemical in the manufacture of nuclear weapons.

What Is Chemical Reactivity?

A chemical reaction is a process by which one or more substances are converted into one or more new substances. It occurs when the atoms of one substance react and gain, lose, or share electrons with the atoms of another substance.

If an atom tends to attract or gain electrons, it is said to be electronegative. If an atom is likely to lose its electron or give it to another substance, it is electropositive. Electronegative elements are typically nonmetals, whereas electropositive elements are metals.

The Pauling scale expresses the value of an element's or substance's electronegativity or electropositivity. If an element has a value greater than 1.8, it is electronegative, and if it has a value less than 1.8, it is electropositive.

Reactivity of Flourine

Fluorine has the highest electronegativity of any element, with a value of 3.98. This means that fluorine, more than any other element, is the most likely to accept electrons. Cesium has the lowest electronegativity of any element at 0.79, making it the least likely to accept electrons, and it even gives its own electrons to others.

In the periodic table, cesium is the most reactive metal while fluorine is the most reactive nonmetal. If you want to know which of these two elements is more reactive, the answer is fluorine. As a result, fluorine is the most reactive of all elements, and there are several reasons for this.

Fluorine is highly reactive, and as a result, it does not exist as a single atom in nature. It is always found as a compound, bonded to other molecules. Even pure fluorine exists as a compound composed of two fluorine atoms bonded together.

Fluorine reacts with almost every element except for helium and neon. The number of elements that react with fluorine is much greater than that of cesium. Cesium does not react with helium, neon, argon, krypton, xenon, and radon. In comparison to oxygen (the element which you think to be the most reactive), oxygen does not react with gold, silver, platinum, helium, neon, argon, nitrogen chlorine, bromine, iodine, astatine, and other elements.

Fluorine is not only reactive with other elements, but it is also reactive in almost all materials. It can corrode things that cannot be corroded and burn noncombustible materials such as metals, glass, rocks, and water. Fluorine is so corrosive that if you fill a house with it, even if it is made of concrete, the house will corrode. If you get caught in a fluorine fire, don't waste time looking for water or a fire extinguisher. These will only serve to exaggerate the fire's intensity. The only way to put out the fire is to cut off the fluorine gas supply.

Fluorine compounds are highly reactive as well. They are even among the most dangerous substances on the planet. Two of the most remarkable fluorine reactive compounds are fluoroantimonic acid and chlorine trifluoride. Chlorine trifluoride is used in the production of rocket fuel and nuclear reactor fuel. When it comes into contact with something, chlorine trifluoride can cause it to burst into flames.

Fluoroanrimonic acid is the most potent acid on the planet. It is extremely corrosive and can corrode almost anything. Its acidity is 20 quintillion (20,000,000,000,000,000,000) times stronger compared to pure sulfuric acid.

Fluorine is reactive with radiation as well. Many attempts to use X-rays to determine the crystal structure of solid fluorine resulted in explosions.

Some Experiments Showing the Reaction of Fluorine With Different Substances

Dangers of Flourine

Fluorine is a highly corrosive, toxic, and hazardous substance. It is a very dangerous material, which is why it is only used and produced in laboratories, and it can only be handled by chemists or chemical experts. Simply inhaling this substance can cause breathing difficulties and respiratory tract damage. In severe cases, it can cause pulmonary edema, circulatory failure, and can be fatal.

When it comes into contact with the skin, it can cause severe skin burns and painful blisters. It can also react with body tissue explosively. Fluorine can harm the kidneys, bones, nerves, and muscles if exposed to it for an extended period of time. It is can also cause death. As a matter of fact, many researchers have died or were injured while working with this substance.

Furthermore, it has the potential to start a fire and explode, resulting in blazing and property damage. It may also pose a risk to the environment.


This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.

© 2022 Errah Caunca