Question

question 7 (2 points)
how many atoms of each element are present in one formula unit of the following compound?
fe₂(so₄)₃

Explanation:

Step1: Determine Fe atoms

The sub - script of Fe is 2, so there are 2 Fe atoms.

Step2: Determine S atoms

The sub - script of S within the sulfate group is 1, and there are 3 sulfate groups. So the number of S atoms is $1\times3 = 3$.

Step3: Determine O atoms

The sub - script of O within the sulfate group is 4, and there are 3 sulfate groups. So the number of O atoms is $4\times3=12$.

Answer:

Fe: 2 atoms, S: 3 atoms, O: 12 atoms