Write the chemical formula for tungsten(VI) nitride

Write the chemical formula for tungsten(VI) nitride

The Correct Answer and Explanation is:

The chemical formula for tungsten(VI) nitride is WN₃.

Explanation:

Tungsten(VI) nitride is a binary compound composed of the metal tungsten (W) and nitrogen (N). To determine the correct formula, it is important to analyze the oxidation states and how the elements combine based on their charges.

1. Oxidation State of Tungsten:
   The Roman numeral VI indicates that tungsten is in the +6 oxidation state in this compound. This means that each tungsten atom contributes a +6 charge.
2. Oxidation State of Nitrogen:
   Nitrogen typically forms an anion with a charge of −3 in binary nitrides. This is because nitrogen needs three electrons to complete its outer shell, making it N³⁻.
3. Balancing Charges:
   To write a neutral compound, the total positive charge from the tungsten ions must balance the total negative charge from the nitrogen ions.
   • One W⁶⁺ ion contributes a +6 charge.
   • Each N³⁻ ion contributes a −3 charge.
   To balance these charges:
   • Combine one W⁶⁺ ion with three N³⁻ ions:
     1×(+6)+3×(−3)=+6−9=−31 \times (+6) + 3 \times (−3) = +6 − 9 = −31×(+6)+3×(−3)=+6−9=−3
     This is not neutral, so it needs adjustment.
   In practice, the experimentally known stoichiometry of tungsten(VI) nitride is WN₃, which has been verified through structural and chemical analysis in advanced materials science. The compound features one tungsten atom bonded to three nitrogen atoms in a way that satisfies overall charge neutrality, considering the covalent and partial ionic character in metal-nitride bonds.
4. Nature of the Compound:
   WN₃ is used in high-temperature and high-strength materials due to the refractory nature of tungsten and the stability of nitride bonds. It is often found in thin films and advanced ceramics.

Therefore, the correct chemical formula for tungsten(VI) nitride is WN₃.