To calculate the total mass of the reactants in the given reaction \( \text{FeCl}_3 + 3\text{H}_2\text{O} \), we first need to determine the mass of each component in the reactants based on the provided atomic masses.
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Calculating the mass of \( \text{FeCl}_3 \):
- The mass of iron (\( \text{Fe} \)) = 56 amu
- The mass of chlorine (\( \text{Cl} \)) = 35 amu
- Since there are 3 chlorine atoms in \( \text{FeCl}_3 \):
- \( \text{Mass of } \text{Cl}_3 = 3 \times 35 = 105 , \text{amu} \)
Total mass of \( \text{FeCl}_3 \): \[ \text{Mass of } \text{FeCl}_3 = \text{mass of Fe} + \text{mass of Cl}_3 = 56 + 105 = 161 , \text{amu} \]
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Calculating the mass of \( 3\text{H}_2\text{O} \):
- The mass of hydrogen (\( \text{H} \)) = 1 amu
- Since there are 2 hydrogen atoms in water and 3 water molecules:
- Total hydrogen mass in \( 3\text{H}_2\text{O} = 3 \times 2 = 6 , \text{H atoms} \)
- \( \text{Mass of } 6\text{H} = 6 \times 1 = 6 , \text{amu} \)
- The mass of oxygen (\( \text{O} \)) = 16 amu
- There is 1 oxygen atom in each water molecule and 3 water molecules:
- Total oxygen mass in \( 3\text{H}_2\text{O} = 3 \times 16 = 48 , \text{amu} \)
Total mass of \( 3\text{H}_2\text{O} \): \[ \text{Mass of } 3\text{H}_2\text{O} = \text{mass of H}_6 + \text{mass of O}_3 = 6 + 48 = 54 , \text{amu} \]
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Total mass of the reactants \( \text{FeCl}_3 + 3\text{H}_2\text{O} \): \[ \text{Total mass} = \text{mass of } \text{FeCl}_3 + \text{mass of } 3\text{H}_2\text{O} = 161 + 54 = 215 , \text{amu} \]
The total mass of the reactants is 215 amu.
Therefore, the correct response is: 215 amu.