Question

Nitrogen can ionically bond with an unknown element X from group 2. How many ions of element X are required to create a stable ionic compound with nitrogen? A) 2 B) 3 C) 4 D) There is not enough information.

Answer 1

To make a stable ionic compound you need 8 valence electrons and since nitrogen has 5 valence electrons he would need 4 more ions of Elements to make a full 8,

Answer 2

Answer is: B) 3.

Nitrogen (nonmetal) in this compound has oxidation number -3 and element X (metal) has oxidation number +2.

Smallest common multiple for 3 and 2 is 6.

number of nitrogen atoms = 6 ÷ 3.

number of nitrogen atoms = 2, there are two nitrogen atoms.

number of atom X: 6 ÷ 2 = 3.

For example, Mg₃N₂ is magnesium nitride. Nitrogen has -3 oxidation number and magnesium has oxidation number +2.