Final answer:
The percent of nitrogen in Li3N is calculated to be 40.20% by dividing the mass of nitrogen by the total mass of the compound and multiplying by 100.
Step-by-step explanation:
To calculate the percent of nitrogen in lithium nitride (Li3N), we will use the atomic masses provided for lithium (Li) and nitrogen (N). First, find the total molecular mass of Li3N by adding the atomic masses of 3 lithium atoms and 1 nitrogen atom:
- Molecular mass of Li = 3 × 6.94 amu = 20.82 amu
- Molecular mass of N = 14.01 amu
- Total molecular mass of Li3N = 20.82 amu + 14.01 amu = 34.83 amu
Next, calculate the percent composition by taking the atomic mass of nitrogen and dividing it by the total molecular mass, then multiply by 100:
% N = (14.01 amu / 34.83 amu) × 100 = 40.20%
Therefore, the percent of nitrogen in Li3N is 40.20%.