The correct answer is D. P4.
Phosphorus is a chemical element with the symbol P and atomic number 15. It is a non-metallic, pale yellow, odorless, tasteless, and highly flammable element. Phosphorus is the most reactive of all the non-metals. It is found in nature in the form of phosphate rocks. Phosphorus is essential for life, as it is a component of DNA, RNA, and ATP.
The molecular formula of a compound tells us the number and type of atoms that make up the compound. The molecular formula of phosphorus is P4. This means that each molecule of phosphorus contains four phosphorus atoms.
The other options are incorrect because they do not represent the correct number of phosphorus atoms in a molecule of phosphorus. Option A, P1, would represent a molecule of phosphorus that contains only one phosphorus atom. Option B, P2, would represent a molecule of phosphorus that contains two phosphorus atoms. Option C, P3, would represent a molecule of phosphorus that contains three phosphorus atoms.
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