To calculate the atomic mass of Fe(OH)₃, you need to account for the contributions from each element in the formula:
- Iron (Fe): 1 atom × 56 amu = 56 amu
- Oxygen (O): 3 atoms × 16 amu = 48 amu (since there are 3 hydroxide groups, OH)
- Hydrogen (H): 3 atoms × 1 amu = 3 amu (again, from the 3 hydroxide groups)
Now, add these contributions together:
\[ 56 \text{ amu (for Fe)} + 48 \text{ amu (for O)} + 3 \text{ amu (for H)} = 107 \text{ amu} \]
Therefore, the atomic mass of Fe(OH)₃ is 107 amu.
The correct response is 107 amu.