Question

Consider again the thermite reaction. If 0.0257 g Al react completely, what mass of Fe forms? Use the periodic table to find molar masses. Fe2O3 + 2Al → Al2O3 + 2Fe Select the correct setup for this calculation.

Answer 1

0.0532 grams

Step-by-step explanation:

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Answer 2

The mass of Fe that is formed is 0.0532 grams

Explanation

Fe2O3 + 2 Al → Al2O3 + 2 Fe

Step 1: find the moles of Al

moles = mass/molar mass

from periodic table the molar mass of Al= 27 g/mol

moles = 0.0257g /27 g/mol =9.5 x10^-4 moles of Al

Step 2: use the mole ratio to determine the moles of Fe

the moles ratio of Al:Fe is 2:2= 1:1

therefore the moles of Fe is also = 9.5 x10 ^-4 moles

Step 3: find the mass of Fe

mass= moles x molar mass of Fe

from periodic table the molar mass of Fe= 56 g/mol

mass= 9.5 x10 ^-4 moles x 56 g/mol =0.0532 grams