Answer:
28.17 %
Step-by-step explanation:
In the question we are required to determine the percent by mass of nitrogen in (NH₄)₃PO₄.
- To calculate the percent by mass of an element in a compound we use the formula;
- % by mass =(Mass of the element÷ Relative formula mass of the compound)100
In this case;
- Atomic mass of nitrogen is 14.0 g/mol
But; There are three nitrogen atoms in (NH₄)₃PO₄.
Therefore; Mass of nitrogen in (NH₄)₃PO₄ = 14.0 × 3
= 42 g
The relative formula mass of (NH₄)₃PO₄ = 149.0867 g/mol
Thus;
% by mass of N = (42 g ÷ 149.0867 g/mo)× 100%
= 28.17 %
Therefore, the % by mass of N is (NH₄)₃PO₄ is 28.17%