argon

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Diagram showing the chemical properties of argon from the periodic table, including atomic number 18, symbol Ar, atomic weight range, electron configuration, noble gas classification, face-centered cubic crystal structure, and gaseous state at room temperature.

Argon isolation

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Line graph showing the first ionization energies of the elements as a function of atomic number, with peaks at noble gases like helium, neon, argon, krypton, xenon, and radon, and labeled elements at key points.

argon phase diagram

Figure 1: The four stable geometric structures of the seven-atom cluster of argon, in order of increasing energy: (A) A pentagonal bipyramid. (B) A regular octahedron with one face capped by the seventh atom. (C) A regular tetrahedron with three of its faces capped by other atoms. (D) A trigonal bipyramid with two of its faces capped by other atoms; although this has the highest energy of the four structures, it is very close in energy to the tricapped tetrahedron.

Figure 2: The four lowest-energy structures of the 13-atom cluster of argon.

At a Glance

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argon: Media

chemical element

Images

Diagram showing the chemical properties of argon from the periodic table, including atomic number 18, symbol Ar, atomic weight range, electron configuration, noble gas classification, face-centered cubic crystal structure, and gaseous state at room temperature.

argon

Properties of argon.

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Argon isolation

Argon isolation

Apparatus for isolation of argon.

Encyclopædia Britannica, Inc.

Line graph showing the first ionization energies of the elements as a function of atomic number, with peaks at noble gases like helium, neon, argon, krypton, xenon, and radon, and labeled elements at key points.

first ionization energies of the elements

First ionization energies of the elements.

Encyclopædia Britannica, Inc.

argon phase diagram

argon phase diagram

Figure 1: Phase diagram of argon.

Encyclopædia Britannica, Inc.

Figure 1: The four stable geometric structures of the seven-atom cluster of argon, in order of increasing energy: (A) A pentagonal bipyramid. (B) A regular octahedron with one face capped by the seventh atom. (C) A regular tetrahedron with three of its faces capped by other atoms. (D) A trigonal bipyramid with two of its faces capped by other atoms; although this has the highest energy of the four structures, it is very close in energy to the tricapped tetrahedron.

Figure 1: The four stable geometric structures of the seven-atom cluster of argon,...

Encyclopædia Britannica, Inc.

Figure 2: The four lowest-energy structures of the 13-atom cluster of argon.

Figure 2: The four lowest-energy structures of the 13-atom cluster of argon.

Encyclopædia Britannica, Inc.

Interactives

Explore an interactive periodic table of the elements

Explore an interactive periodic table of the elements

Periodic table of the elements.

Encyclopædia Britannica, Inc.

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