Answer:
17.07%
Step-by-step explanation:
We'll begin by calculating the molar mass of calcium nitrate, Ca(NO₃)₂. This can be obtained as follow:
Molar mass of Ca(NO₃)₂ = 40 + 2[14 + (3×16)]
= 40 + 2[14 + 48]
= 40 + 2[62]
= 40 + 124
= 164 g/mol
Next, we shall determine the mass of nitrogen (N) in Ca(NO₃)₂. This can be obtained as follow:
There are 2 moles of N in Ca(NO₃)₂. Therefore, the mass of N in Ca(NO₃)₂ can be obtained as follow:
Mass of N in Ca(NO₃)₂ = 2 × 14 = 28 g
Finally, we shall determine percentage by mass of N in Ca(NO₃)₂. This can be obtained as follow:
Molar mass of Ca(NO₃)₂ = 164 g/mol
Mass of N in Ca(NO₃)₂ = 28 g
Mass percentage of N =
Mass percentage of N = mass of N / Molar mass of Ca(NO₃)₂ × 100
Mass percentage of N = 28/164 × 100
Mass percentage of N = 17.07%