Which of the following represents magnesium nitrate?

Magnesium nitrate is represented by the formula Mg(NO3)2. This compound is composed of magnesium ions (Mg²⁺) and nitrate ions (NO3⁻).

In this structure, magnesium has a +2 charge. To achieve electrical neutrality in the compound, two nitrate ions, each with a -1 charge, are needed. Hence, the correct formula includes one magnesium ion paired with two nitrate ions, resulting in the formula Mg(NO3)2.

Understanding the composition of the nitrate ion, which consists of one nitrogen atom bonded to three oxygen atoms, is critical for identifying the formula accurately. The formula reflects the stoichiometric balance required to ensure the overall charge of the compound is zero, illustrating that two units of the nitrate ion are necessary to balance the +2 charge of the magnesium ion.