What is the formula mass for (NH4)3PO4
To find the formula mass of (NH4)3PO4, also known as ammonium phosphate, you need to calculate the sum of the atomic masses of each element present in the compound.
Step 1: Determine the Atomic Mass of Each Element
Refer to the periodic table of elements and find the atomic masses of the elements in the compound:
The atomic mass of nitrogen (N) is approximately 14.01 atomic mass units (amu).
The atomic mass of hydrogen (H) is approximately 1.01 amu.
The atomic mass of phosphorus (P) is approximately 30.97 amu.
The atomic mass of oxygen (O) is approximately 16.00 amu.
Step 2: Determine the Number of Each Element
Next, identify the number of each element present in the compound. The subscript numbers in the compound's formula indicate the number of atoms of each element.
In (NH4)3PO4, there are:
- Three ammonium ions (NH4+), each containing one nitrogen atom and four hydrogen atoms.
- One phosphate ion (PO4^3-), which contains one phosphorus atom and four oxygen atoms.
Step 3: Calculate the Formula Mass
Multiply the atomic mass of each element by the number of atoms present and add them together to find the formula mass.
(NH4)3PO4 formula mass = (3 x Number of nitrogen atoms x Atomic mass of nitrogen) + (12 x Number of hydrogen atoms x Atomic mass of hydrogen) + (1 x Number of phosphorus atoms x Atomic mass of phosphorus) + (4 x Number of oxygen atoms x Atomic mass of oxygen)
= (3 x 1 x 14.01 amu) + (12 x 4 x 1.01 amu) + (1 x 1 x 30.97 amu) + (4 x 16.00 amu)
= 42.03 amu + 48.48 amu + 30.97 amu + 64.00 amu
= 185.48 amu
Therefore, the formula mass of (NH4)3PO4 is approximately 185.48 atomic mass units.