What is the formula and name of the compound formed between Mg and P? Select one:
A Mgâ‚‚P3; Magnesium (II) Phosphide
B Mg3P2; Magnesium Phosphide
C Mg3Pâ‚‚; Tri Magnesium Di Phosphide
D Mg2P3; Magnesium Phosphide
The Correct Answer and Explanation is :
The correct answer is B: Mg₃P₂; Magnesium Phosphide.
Explanation:
When magnesium (Mg) combines with phosphorus (P), they form an ionic compound, magnesium phosphide. To understand how this compound forms, let’s examine the valence electron configuration of both elements and how they interact:
- Magnesium (Mg) is an alkaline earth metal in Group 2 of the periodic table. It has an atomic number of 12 and an electron configuration of [Ne] 3s². Since magnesium is in Group 2, it readily loses two electrons to achieve a stable electron configuration, similar to the nearest noble gas (Neon). This results in a Mg²⁺ ion.
- Phosphorus (P) is a non-metal in Group 15 with an atomic number of 15 and an electron configuration of [Ne] 3s² 3p³. Phosphorus tends to gain three electrons to achieve a stable electron configuration, similar to the nearest noble gas (Argon), resulting in a P³⁻ ion.
When magnesium and phosphorus combine, the Mg²⁺ ions and P³⁻ ions come together in a way that the charges balance out. For every three Mg²⁺ ions, two P³⁻ ions are needed to neutralize the charges. This results in the formula Mg₃P₂, where:
- 3 magnesium ions (Mg²⁺) contribute a total charge of +6.
- 2 phosphorus ions (P³⁻) contribute a total charge of -6.
Thus, the ionic compound formed is Magnesium Phosphide (Mg₃P₂), which has a ratio of three magnesium ions to two phosphorus ions.
The other options listed are incorrect because they do not maintain charge balance:
- A (Mg₂P₃) and D (Mg₂P₃) would result in an unbalanced charge distribution.
- C (Mg₃P₂) is the correct formula and is also the name of the compound.
Therefore, the compound formed between magnesium and phosphorus is correctly named Magnesium Phosphide, and its formula is Mg₃P₂.