Write the formula for manganese(II) nitride.
The correct answer and explanation is:
Correct Answer: Mn₃N₂
Manganese(II) nitride is a compound formed by the combination of manganese ions and nitride ions. To write the correct chemical formula, it is important to understand the oxidation states of the elements involved and how to balance their charges.
Manganese(II) means manganese is in the +2 oxidation state, which is represented as Mn²⁺. The nitride ion is derived from nitrogen and has a charge of -3, written as N³⁻.
In order to form a neutral compound, the total positive and negative charges must balance. To achieve this balance, find the least common multiple of the charges. The least common multiple of 2 and 3 is 6.
To get a total positive charge of +6, three Mn²⁺ ions are needed:
3 × (+2) = +6
To get a total negative charge of -6, two N³⁻ ions are needed:
2 × (−3) = −6
Combining three manganese(II) ions with two nitride ions results in a neutral compound. Therefore, the formula is written as Mn₃N₂.
This formula indicates that the compound contains three manganese atoms and two nitrogen atoms. It is an example of an ionic compound formed between a transition metal and a nonmetal. Manganese, being a transition metal, can have multiple oxidation states, so it is important to specify the oxidation state using Roman numerals in the compound’s name. In this case, the Roman numeral II shows that manganese has a +2 charge.
Understanding how to balance charges in ionic compounds is essential in inorganic chemistry. It helps ensure that the resulting formula represents a neutral compound and reflects the correct proportions of each ion.