The elements that are almost completely unreactive are the noble gases in group 18.
Inert gases. This was a common term for them until the first reaction between a noble gas and another material was discovered a few decades ago.
Metals and nonmetals are shaped to suit the task in hand. They may be almost any shape.
Fluorine is more reactive than radon. Fluorine is a highly reactive nonmetal, while radon is a noble gas that is fairly unreactive. Fluorine readily reacts with almost all other elements, while radon is less likely to undergo chemical reactions.
Uranus
Noble gases or group 18 elements
Inert Gases
Fluorine is the most chemically active nonmetal on the planet. It is highly reactive and can form compounds with almost all elements due to its strong electronegativity.
All or almost all of the nonmetal and metalloid elements that are not noble gases have this property. All the halogens, oxygen, nitrogen, and carbon all form many compounds with other elements as well as polyatomic allotropes of the elements themselves at standard temperature and pressure.
Reaction between a metal oxide and a nonmetal oxide to produce a salt containing at least three elements is a synthesis reaction. The salt almost always contains at least one monatomic metal cation and at least one polyatomic anion that contains all of the elements of the reacted nonmetal oxide plus the oxygen atoms from the metal oxide. This type of anion is called an "oxyanion" or the "anion of an oxyacid."
Inert gases. This was a common term for them until the first reaction between a noble gas and another material was discovered a few decades ago.
The Group 0 elements are called the noble gases. These are the six gases that are almost completely inert. Since they do not lose or gain any electrons, their valence is 0.
The noble gases are among the most nonreactive elements. This group includes helium, neon, argon, krypton, xenon, and radon. They have full valence electron shells, making them stable and unlikely to form chemical bonds with other elements.
The elements in group 8 - the noble gases (helium, neon, argon, krypton, xenon and radon) - are completely unreactive, as they have a complete outermost energy level ie. a perfect electron configuration.
Reaction between a metal oxide and a nonmetal oxide to produce a salt containing at least three elements is a synthesis reaction. The salt almost always contains at least one monatomic metal cation and at least one polyatomic anion that contains all of the elements of the reacted nonmetal oxide plus the oxygen atoms from the metal oxide. This type of anion is called an "oxyanion" or the "anion of an oxyacid."
Fluorine and oxygen are the most chemically reactive nonmetals. Fluorine is the most reactive nonmetal, readily reacting with almost all other elements, while oxygen is highly reactive and forms compounds with most elements in the periodic table.
The element that forms compounds with all other elements except helium, neon, and argon is fluorine. Fluorine is the most reactive nonmetal and readily forms compounds with almost all other elements due to its strong electron-attracting abilities.
Neon is a nonreactive gas. As it is a gas, it would only be found naturally (on earth) as a liquid if it were cooled down a LOT. There is no gas that is more dense than a liquid. Also, being nonreactive, neon doesn't bond with other elements without a LOT of energy, and even then, it is extremely unstable, so it would almost always be found as a gas. So, neon would be found in the air, or in gas pockets underground.