The molar mass of Fe(OH)3 is 106.87 g/mol. How many moles of H2SO4 are needed to react completely with 5.419 g of Fe(OH)3?

To find the number of moles of H2SO4 needed to react completely with 5.419 g of Fe(OH)3, we will follow these steps:

Step 1: Determine the molar mass of Fe(OH)3
The molar mass of Fe(OH)3 can be calculated by summing up the atomic masses of its constituent elements. Iron (Fe) has an atomic mass of 55.845 g/mol, oxygen (O) has a molar mass of 16.00 g/mol, and hydrogen (H) has an atomic mass of 1.008 g/mol. Since there are three hydroxide (OH) groups in the compound, we multiply the molar mass of OH (16.00 + 1.008) by 3.

Fe(OH)3:
Fe = 55.845 g/mol
O = 16.00 g/mol
H = 1.008 g/mol
OH = 16.00 + 1.008 = 17.008 g/mol
Fe(OH)3 = (55.845) + 3(17.008) = 106.87 g/mol

Step 2: Convert the given mass of Fe(OH)3 to moles
To convert grams to moles, we will use the formula:

moles = mass (g) / molar mass (g/mol)

moles of Fe(OH)3 = 5.419 g / 106.87 g/mol = 0.0506 mol

Step 3: Apply the stoichiometry of the balanced chemical equation
The balanced chemical equation for the reaction between Fe(OH)3 and H2SO4 is:

Fe(OH)3 + 3H2SO4 -> Fe2(SO4)3 + 6H2O

According to the equation, 1 mole of Fe(OH)3 reacts with 3 moles of H2SO4. Therefore, since we have 0.0506 moles of Fe(OH)3, we will need:

moles of H2SO4 = 0.0506 mol x (3 mol H2SO4 / 1 mol Fe(OH)3) = 0.1518 mol

So, to completely react with 5.419 g of Fe(OH)3, we will need 0.1518 moles of H2SO4.