Calculate the percentage by mass of nitrogen in calcium trioxonitrate (V)
[Ca = 40, N = 14, O = 16]
A
8.5%
B
13.1%
C
17.1%
D
27.6%
Verified Correct Answer: C.
Step-by-Step Mathematical Solution
Calcium trioxonitrate(V) is (CaNO\(_3\))\(_2\)
The molecular mass of CaNO\(_3\))\(_2\) = 40 + (14 + (16 X 3)) x 2 = 164
Relative molecular mass of nitrogen(N\(_2\)) = 14 x 2 = 28
% by mass of nitrogen in CaNO\(_3\))\(_2\) = \(\frac{28}{164}\) x \(\frac{100}{1}\)
= 17.073 ≈ 17.1%
Source: WAEC / JAMB / NECO Classroom Archive (Record #4464)