To find the total mass of the reactants in the reaction:
\[ \text{FeCl}_3 + 3\text{H}_2\text{O} \rightarrow \text{Fe(OH)}_3 + 3\text{HCl} \]
we need to calculate the mass of each reactant:
-
Mass of FeCl₃:
- Fe = 56 amu
- Cl = 35 amu (there are 3 Cl atoms, so multiply by 3)
- Total mass of FeCl₃ = Mass of Fe + (3 × Mass of Cl)
- = 56 + (3 × 35)
- = 56 + 105
- = 161 amu
-
Mass of 3H₂O:
- H = 1 amu (there are 2 H atoms in water, so multiply by 2)
- O = 16 amu (there is 1 O atom)
- Mass of H₂O = (2 × Mass of H) + Mass of O
- = (2 × 1) + 16
- = 2 + 16
- = 18 amu
- Therefore, for 3 H₂O: 3 × 18 = 54 amu
Now, combine the masses of both reactants:
\[ \text{Total mass of reactants} = \text{mass of FeCl}_3 + \text{mass of 3H}_2\text{O} \] \[ = 161 , \text{amu} + 54 , \text{amu} = 215 , \text{amu} \]
Thus, the total mass of the reactants is 215 amu.
So the correct response is: 215 amu.