Question

Magnesium reacts with an element (X) to form an ionic compound. If the ground state electronic configuration of (X) is 1s² 2s² 2p³ , the simplest formula for this compound is

• A. Mg₂X₃
• B. Mg₂X
• C. MgX₂
• D. Mg₃X₂

Answer 1

The Correct Option is A

To determine the simplest formula for the ionic compound formed between magnesium (Mg) and element X, we need to analyze the electronic configurations and typical charges of the involved elements:

1. Electronic Configuration: Magnesium (Mg) has the atomic number 12. Its electronic configuration is 1s² 2s² 2p⁶ 3s². This means magnesium tends to lose two electrons to achieve a noble gas configuration, resulting in a Mg²⁺ ion.

2. The element X has an electronic configuration of 1s² 2s² 2p³, which corresponds to nitrogen with the atomic number 7. To achieve stability with a noble gas configuration (1s² 2s² 2p⁶), it needs to gain three electrons, forming an X^3- ion.

3. Combining Ions: The charges of Mg²⁺ and X^3- need to balance when they form an ionic compound. Thus, the smallest number of Mg and X that bring their charges into balance are two Mg²⁺ ions and three X^3- ions.

   This yields a total charge balance of 2(Mg²⁺) + 3(X^3-) = 0, resulting in the compound Mg₃X₂.

4. Conclusion: Thus, the simplest formula for the compound formed from Mg and X is Mg₃X₂.