To determine the approximate number of atoms in a given mass of a substance, you need to use Avogadro's constant and the molar mass of the substance.
Avogadro's constant, denoted as Nₐ, is approximately 6.022 × 10²³ particles per mole. The molar mass of iron (Fe) is about 55.85 grams per mole.
To calculate the number of atoms in 35 grams of Fe, we can follow these steps:
Determine the number of moles of Fe: Moles of Fe = Mass of Fe / Molar mass of Fe = 35 g / 55.85 g/mol
Calculate the number of atoms using Avogadro's constant: Number of atoms = Moles of Fe × Avogadro's constant
Plugging in the values, we have:
Number of atoms = (35 g / 55.85 g/mol) × (6.022 × 10²³ particles/mol)
Performing the calculation, we get:
Number of atoms ≈ 3.827 × 10²³ atoms
Therefore, there are approximately 3.827 × 10²³ atoms in 35 grams of iron (Fe).