Answer:
Step-by-step explanation:
To calculate the mass of 1.57 moles of iron(III) oxide, we need to know the molar mass of iron(III) oxide, which can be calculated by adding up the atomic masses of all the atoms in one mole of the compound.
The formula for iron(III) oxide is Fe2O3, which consists of two iron atoms and three oxygen atoms.
The atomic mass of iron is 55.845 g/mol, and the atomic mass of oxygen is 15.999 g/mol.
Therefore, the molar mass of Fe2O3 is:
(2 x 55.845 g/mol) + (3 x 15.999 g/mol) = 159.69 g/mol
Now we can calculate the mass of 1.57 moles of Fe2O3 by multiplying the molar mass by the number of moles:
1.57 moles x 159.69 g/mol = 251.05 g
So the mass of 1.57 moles of iron(III) oxide is 251.05 grams.