Answer:

Explanation:
Iron is Fe, nitrogen is N. Nitrogen is diatomic, which means it occurs as a molecular pair by itself. Iron III nitride has a chemical formula of FeN because nitrogen has a charge of 3-, and iron III tells us the iron has a charge of 3+ so you just need one of each to make the charges balance and the compound neutral.
Potassium ......................
The volume of one mole of any gas at Standard Temperature and Pressure (1 atm and 0 degrees Celsius [273K]) is 22.4 L.
Mass divide by volume
M
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V