What is the formula for cobalt(IV) nitride
The Correct Answer and Explanation is:
Formula for cobalt(IV) nitride: Co₃N₄
Explanation:
To determine the correct chemical formula for cobalt(IV) nitride, we need to consider the charges of the ions involved and apply the rules of ionic compound formation.
1. Understanding the Ions:
- Cobalt(IV): The Roman numeral IV indicates that cobalt has a +4 oxidation state. Therefore, the cobalt ion is written as Co⁴⁺.
- Nitride: The nitride ion is the anion form of nitrogen. Nitrogen gains three electrons to achieve a full octet, forming the nitride ion with a charge of −3. This is written as N³⁻.
2. Balancing the Charges:
Ionic compounds are electrically neutral. The total positive charge must equal the total negative charge. To balance the +4 charge of cobalt and the −3 charge of nitride, we need to find the least common multiple (LCM) of the two charges.
- The LCM of 4 and 3 is 12.
- To reach +12, we need three Co⁴⁺ ions: 3 × (+4) = +12.
- To reach −12, we need four N³⁻ ions: 4 × (−3) = −12.
3. Writing the Formula:
From the ratio above, we combine three cobalt(IV) ions with four nitride ions to make the compound neutral. This gives the formula Co₃N₄.
4. Naming and Usage Notes:
The name cobalt(IV) nitride reflects the oxidation state of cobalt. Transition metals often have multiple oxidation states, so Roman numerals are used to specify which one is involved. Cobalt(IV) compounds are less common and tend to be more reactive than cobalt(II) or cobalt(III) compounds. Nitrides are generally hard, high-melting-point materials and may be used in ceramics or electronic applications.
Thus, Co₃N₄ is the correct and balanced chemical formula for cobalt(IV) nitride.
