From the Periodic table, it can be determined that iron (Fe) has an atomic mass of 56 amu, oxygen (O) has an atomic mass of 16 amu, and hydrogen (H) has a mass of 1 amu. What would the atomic mass of Fe(OH) 3

Question

be?(1 point)
Responses

107 amu
107 amu

73 amu
73 amu

75 amu
75 amu

219 amu

Answer 1

To calculate the atomic mass of Fe(OH)₃, we need to add the atomic masses of iron (Fe), oxygen (O), and hydrogen (H) in the formula.

1. The atomic mass of iron (Fe) = 56 amu.
2. The atomic masses of oxygen (O) and hydrogen (H):
   • Each hydroxide group (OH) contains one oxygen and one hydrogen.
   • The atomic mass of oxygen (O) = 16 amu.
   • The atomic mass of hydrogen (H) = 1 amu.

Since there are three hydroxide groups in Fe(OH)₃, we can find the total mass contributed by the hydroxide groups:

\[ \text{Total mass of OH groups} = 3 \times (\text{mass of O} + \text{mass of H}) = 3 \times (16 , \text{amu} + 1 , \text{amu}) = 3 \times 17 , \text{amu} = 51 , \text{amu} \]

Now, we add the mass of iron to the total mass of the hydroxide groups:

\[ \text{Total mass of Fe(OH)₃} = \text{mass of Fe} + \text{total mass of OH groups} = 56 , \text{amu} + 51 , \text{amu} = 107 , \text{amu} \]

Thus, the atomic mass of Fe(OH)₃ is 107 amu.