Phosphorus vapor is composed of ___________________?
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Answer: D. P4
Explanation
At lower temperatures and in the vapor phase, elemental phosphorus exists as discrete tetrahedral molecules. Each tetrahedral molecule contains four phosphorus atoms bound together with the chemical formula P4. This molecular structure distinguishes phosphorus vapor from diatomic gases like nitrogen or oxygen. Elemental phosphorus is a highly reactive non-metal that exhibits several distinct allotropic structural forms. White phosphorus consists of reactive P4 tetrahedral molecules that ignite spontaneously in warm air. At very high temperatures, P4 molecules dissociate into smaller diatomic P2 molecular species.
Industrial production of phosphoric acid and phosphorus derivatives involves handling white phosphorus vapor safely. Condensation units cool phosphorus vapor underwater to prevent oxidation and fires during chemical processing. Understanding molecular vapor composition is important for thermodynamic calculations in chemical reactor design. P is atomic phosphorus, which only exists at extremely high temperatures under conditions of severe dissociation. P2 is a diatomic phosphorus molecule formed only at elevated thermal dissociation temperatures above 800 degrees Celsius. P3 is not a stable allotropic form or vapor phase molecular structure for elemental phosphorus.
- Subject
- Engineering
- Category
- Chemical Engineering
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- —
- Difficulty
- medium
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