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Fractional distillation is a sophisticated process utilized in the separation of mixtures into their individual components, based on differences in boiling points. In the context of isolating noble gases, fractional distillation assumes a pivotal role.

The residual gases, following the removal of the predominant components such as nitrogen and oxygen, are left with a composition that largely includes the noble gases—each with its unique boiling point. By gradually lowering the temperature within a distillation column, these gases are induced to liquefy at various levels, allowing for their individual extraction.

For instance, argon liquefies at around -185.9°C, while neon does so at around -246.1°C. Through meticulous control of temperature within the distillation setup, we can isolate these gases one by one, collecting them in their pure form.

Air collection serves as the fundamental step in isolating noble gases. It involves procuring an air sample from the atmosphere. To ensure a representative sample, the collection is usually done away from areas with significant pollution to minimize contamination from industrial emissions.

Once collected, the air constitutes not only the noble gases—which include helium, neon, argon, krypton, xenon, and radon—but also a mix of other gases such as nitrogen, oxygen, carbon dioxide, and trace amounts of water vapor and other compounds. The initial phase of the process is dedicated to the careful collection of this air without altering its composition.

The removal of atmospheric gases is an essential precursor to the isolation of noble gases. Oxygen and nitrogen, which dominate the atmospheric composition, must be extracted due to their significant presence.

To remove oxygen, it can be reacted with hot hydrogen to form water vapor—effectively reducing its concentration. The resultant water vapor is then condensed and subsequently removed. Nitrogen, being relatively unreactive, is typically left until further processing is possible. Other components like carbon dioxide and water vapor are also condensed and removed by reducing the temperature, which prevents them from interfering in the subsequent fractional distillation of noble gases.

Noble gas separation is the final objective in the process of isolating these elusive elements from the air. After the removal of major atmospheric gases, what remains is a mixture primarily containing noble gases, each with their own characteristic physical properties.

The utilization of fractional distillation allows us to exploit the distinct boiling points of these gases. By systematically managing the temperature in a way that one gas liquefies at a time, the noble gases can be separated from the mixture. This careful tuning of conditions ensures that gases like helium, neon, argon, krypton, and xenon can be isolated in their purest forms for both scientific and industrial applications.