How many grams are in 8.2x10 to the power of 22 molecules of Fe2O3?
To determine the number of grams in a given number of molecules, you would need to use the concept of Avogadro's number and the molar mass of the compound.
1. Start by identifying the molar mass of Fe2O3 (iron(III) oxide). The molar mass of Fe2O3 is calculated by adding up the atomic masses of its constituent elements:
- Atomic mass of Fe (iron) = 55.845 g/mol
- Atomic mass of O (oxygen) = 15.999 g/mol (There are three oxygen atoms in Fe2O3)
Therefore, the molar mass of Fe2O3 is:
Molar mass of Fe2O3 = (2 × atomic mass of Fe) + (3 × atomic mass of O) = (2 × 55.845 g/mol) + (3 × 15.999 g/mol) = 159.69 g/mol
2. Use Avogadro's number to convert the number of molecules to moles. Avogadro's number (NA) is approximately 6.022 × 10^23.
Moles of Fe2O3 = (Number of molecules) / (Avogadro's number)
= 8.2 × 10^22 / 6.022 × 10^23
= 0.136 mol
3. Finally, use the molar mass of Fe2O3 to convert moles to grams:
Grams of Fe2O3 = (Moles of Fe2O3) × (Molar mass of Fe2O3)
= 0.136 mol × 159.69 g/mol
= 21.7 g
Therefore, there are 21.7 grams in 8.2 × 10^22 molecules of Fe2O3.