Write the formula for the compound copper (II) nitride..
a. Cu₂N3
b. CuN
c. CuN₂
d. Cu3N₂
The Correct Answer and Explanation is:
The correct formula for copper (II) nitride is Cu₃N₂.
Explanation:
Copper (II) nitride is a compound formed between copper (Cu) and nitrogen (N). To determine the correct formula, we need to consider the oxidation states of the elements involved and balance their charges to ensure the compound is electrically neutral.
- Oxidation States:
- Copper (Cu) can have multiple oxidation states, but in the case of copper (II) nitride, copper is in the +2 oxidation state. This means each copper atom contributes a charge of +2.
- Nitrogen (N) typically forms a nitride ion (N³⁻) when it is in its most common oxidation state, which is -3.
- Balancing Charges:
To form a neutral compound, the total positive charge must equal the total negative charge. Since copper (II) has a +2 charge, and nitrogen (N) has a -3 charge, we need to balance the charges:
- The total positive charge from two copper atoms (each with a +2 charge) will be ( 2 \times (+2) = +4 ).
- The total negative charge from three nitride ions (each with a -3 charge) will be ( 2 \times (-3) = -6 ). To achieve charge neutrality, the formula for copper (II) nitride will consist of three copper ions (Cu) for every two nitride ions (N). Thus, the formula is Cu₃N₂.
This formula shows that there are three copper (Cu) ions for every two nitrogen (N) ions, which balances the +6 charge from copper and the -6 charge from nitrogen, resulting in a neutral compound.
Therefore, the correct answer is d. Cu₃N₂.