Which of the following nitrogen-containing compounds would supply the most nitrogen per gram of fertilizer?
a. iron azide, Fe(N3)2, MW = 140 g/mol
b. sodium azide, NaN3, MW = 65 g/mol
c. potassium nitrite, KNO2, MW = 85.1 g/mol
d. potassium azide, KN3, MW = 81.1 g/mol
e. There is not enough information to answer this problem
To determine which of the given nitrogen-containing compounds would supply the most nitrogen per gram of fertilizer, we need to calculate the amount of nitrogen in each compound.
The atomic weight of nitrogen is approximately 14 g/mol. We'll use this value to determine the amount of nitrogen in a certain molecule.
Let's calculate the nitrogen content for each compound:
a. iron azide, Fe(N3)2, MW = 140 g/mol
- Iron azide contains 2 nitrogen atoms.
- The nitrogen content = 2 nitrogen atoms x 14 g/mol = 28 g/mol.
b. sodium azide, NaN3, MW = 65 g/mol
- Sodium azide contains 1 nitrogen atom.
- The nitrogen content = 1 nitrogen atom x 14 g/mol = 14 g/mol.
c. potassium nitrite, KNO2, MW = 85.1 g/mol
- Potassium nitrite contains 1 nitrogen atom.
- The nitrogen content = 1 nitrogen atom x 14 g/mol = 14 g/mol.
d. potassium azide, KN3, MW = 81.1 g/mol
- Potassium azide contains 3 nitrogen atoms.
- The nitrogen content = 3 nitrogen atoms x 14 g/mol = 42 g/mol.
Comparing the nitrogen content of each compound, we find that:
- Iron azide supplies 28 g of nitrogen per gram of fertilizer.
- Sodium azide and potassium nitrite both supply 14 g of nitrogen per gram of fertilizer.
- Potassium azide supplies 42 g of nitrogen per gram of fertilizer.
Therefore, the compound that supplies the most nitrogen per gram of fertilizer is potassium azide, which has a nitrogen content of 42 g/mol. Thus, the answer is option d.