Write the Lewis Structures for magnesium (Mg) combining with phosphorus (P) to create an ionic compound. (show the transfer of electrons)
The correct answer and explanation is:
The combination of magnesium (Mg) and phosphorus (P) forms an ionic compound, magnesium phosphide (Mg₃P₂). Let’s break down the process of creating the Lewis structure for this compound, focusing on the electron transfer.
Step 1: Electron Configuration
Magnesium (Mg) is in Group 2 of the periodic table and has two valence electrons. Phosphorus (P) is in Group 15 and has five valence electrons.
Step 2: Electron Transfer
Since magnesium has two valence electrons, it will lose both electrons to achieve a stable electron configuration like the nearest noble gas (Neon, which has a full octet). When magnesium loses its two electrons, it becomes a positively charged ion, Mg2+\text{Mg}^{2+}.
Phosphorus, on the other hand, has five valence electrons and needs three more electrons to complete its octet. It will accept these electrons from the magnesium atoms, becoming a negatively charged ion, P3−\text{P}^{3-}.
Step 3: Forming Magnesium Phosphide
To achieve charge neutrality, we need to balance the charges of the ions. Since each magnesium atom loses two electrons and forms a Mg2+\text{Mg}^{2+} ion, two magnesium ions will be required for every phosphorus ion. This results in the formula Mg3P2\text{Mg}_3\text{P}_2, where three magnesium ions balance the charge of two phosphorus ions.
Step 4: Drawing the Lewis Structure
- Magnesium (Mg) will have two electrons in its outer shell, which it will lose to become Mg2+\text{Mg}^{2+}.
- Phosphorus (P) will gain three electrons, filling its valence shell to become P3−\text{P}^{3-}.
- The Mg2+\text{Mg}^{2+} ions and P3−\text{P}^{3-} ions are held together by ionic bonds, as opposite charges attract.
Conclusion
In the ionic compound magnesium phosphide (Mg₃P₂), each magnesium atom donates two electrons to phosphorus, resulting in a stable ionic structure with a 3:2 ratio of magnesium to phosphorus ions. This electron transfer leads to the formation of a neutral compound, where the charges of the ions cancel each other out.