Question

How many valence electrons does each noble gas have?

Answer 1

In periodic table, the noble gases are exactly the members of group 18. Noble gases are typically highly unreactive except when under particular extreme conditions.

Complete answer:
noble gases are a class of chemical element with similar properties, under standard condition they are all odorless, colorless, monatomic gases with very low chemical reactivity. There are six naturally occuring noble gases are helium (He), neon (Ne), argon (Ar), Krypton (Kr), xenon (Xe) and the radioactive radon (Rn).
Valence electron is an outer shell electron that is associated with an atom, and that can participate in the formation of a chemical bond if the outer shell is not closed in a single covalent bond, both atoms contribute one valence electron in order to form a shared pair. For a main group element a valence electron can exist only in the outermost shell, for a transition metal, a valence electron can also be in an inner shell. The presence of valence electrons can determine the element’s chemical properties such as its valence whether it may bond with another element and if so how readily and with how many.
Noble gas has a group 18, the configuration of electrons of every element is such that the outermost shell of the atom is full which implies that it does not have any electron to donate or accept. Noble gases can be well explained by modern theories of atomic structure; their outer shell of valence electrons is considered to be full giving them little tendency to participate in chemical reaction. The internes of noble gasses make them very suitable in applications where reactions are not wanted.

Additional Information:
The discovery of the noble gasses aided in the development of a general understanding of atomic structure. In 1895, French chemist Henri Moissan attempted to form a reaction between fluorine, the most electronegative element and argon, one of the noble gases, but failed. Neil Bohr proposed in 1913 that the electrons in atoms are arranged in shells surrounding the nucleus, and that for all noble gasses except helium the outermost shell always contains eight electrons. In 1916, Gilbert N. Lewis formulated the octet rule, which concluded an octet of electrons in the outer shell was the most stable arrangement for any atom, this arrangement caused them to be unreactive with other elements since they did not require any more electrons to complete their outer shell. Food is packed to insert gas to remove oxygen gas. This presents bacteria from growing. It also presents chemical oxidation by oxygen in normal air.

Note: The inert gas system is used to prevent the atmosphere in cargo tanks or bunkers from coming into the expansion range. In a chemical manufacturing plant, reaction can be conducted under inert gas to minimize fire hazards or unwanted reactions. The inert gases are obtained by fractional distillation to air, with the exception of helium which is separated from a few natural gas sources rich in this element, through cryogenic distillation or membrane separation. All the group 18 elements occur in a free state in the atmosphere. They have high positive electron gain enthalpy and high ionization enthalpy. In gas tungsten arc welding insert gases are used to shield the tungsten from contamination. In underwater diving, insert gas is a component of the breathing mixture which is not metabolically active and serves to dilute the gas mixture.