Calculate the number of iron atoms in a piece of iron weighing `2.8 g` (Atomic mass of iron `= 56 u`).

Explanation

To calculate the number of iron atoms in a piece of iron weighing 2.8 g, we can follow these steps:

### Step 1: Understand the relationship between mass, moles, and atoms
According to the mole concept, one mole of an element is equal to its atomic mass in grams and contains Avogadro's number of atoms (approximately \(6.022 \times 10^{23}\) atoms).

### Step 2: Identify the atomic mass of iron
The atomic mass of iron (Fe) is given as 56 u (atomic mass units). This means that 1 mole of iron weighs 56 grams and contains \(6.022 \times 10^{23}\) atoms.

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