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
- Mg2X3
- MgX2
- Mg2X
- Mg3X2
Answer
(4) Mg3X2
Solution
1s2 2s2 2p3 ⇒ X has 5 valence electrons (nitrogen); it gains 3 electrons to complete its octet ⇒ X3-
Mg loses 2 electrons ⇒ Mg2+
Balancing the charges: 3 (+2) = 2 (-3)
∴ Formula = Mg3X2 (like Mg3N2, formed when Mg burns in nitrogen)
Answer: (4)