How many atoms are present in a sample of pure iron with a mass of 300 g? (The atomic mass of iron = 56 and N_A = 6.02 x 10²³) A)1.8 x 10¹⁹ B)6.7 x 10²² C)1.6 x 10²⁸ D)3.2 x 10²⁴

Question

Quizplus · Accepted Answer

First, calculate the number of moles of iron present in the sample:

moles = mass/molar mass = 300/56 = 5.36 mol

Next, use Avogadro's number to calculate the number of atoms:

number of atoms = moles × Avogadro's number = 5.36 × 6.02 × 10^23 = 3.22 × 10^24

Therefore, the answer is D.

How Many Atoms Are Present in a Sample of Pure