Number of atoms in 560 g of `Fe ("atomic mass 56 g mol"^(-1))`

Options

A. twice that o f70 g N
B. half that of 20 g H
C. half that of 70 g
D. twice that of 40 N

Explanation

To find the number of atoms in 560 g of iron (Fe), we can follow these steps:

### Step 1: Calculate the number of moles of iron
To calculate the number of moles, we use the formula:

\[ \text{Number of moles} = \frac{\text{Given mass (g)}}{\text{Molar mass (g/mol)}} \]

Given:
- Mass of iron (Fe) = 560 g
- Molar mass of iron = 56 g/mol

Substituting the values:

\[ \text{Number of moles} = \frac{560 \, \text{g}}{56 \, \text{g/mol}} = 10 \, \text{moles} \]

### Step 2: Calculate the number of atoms
Now, we know that 1 mole of any substance contains \(6.022 \times 10^{23}\) entities (Avogadro's number). Therefore, to find the number of atoms in 10 moles of iron, we use the formula:

\[ \text{Number of atoms} = \text{Number of moles} \times \text{Avogadro's number} \]

Substituting the values:

\[ \text{Number of atoms} = 10 \, \text{moles} \times 6.022 \times 10^{23} \, \text{atoms/mole} \]

Calculating this gives:

\[ \text{Number of atoms} = 6.022 \times 10^{24} \, \text{atoms} \]

### Final Answer
The number of atoms in 560 g of iron is \(6.022 \times 10^{24}\) atoms.

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