Number of Fe atoms in 100 g Haemoglobin if it contains 0.33% Fe. (Atomic mass of Fe. = 56)

Options

A. ` 0.035 xx 10^(23)`
B. 35
C. ` 3.5 xx 10^(23)`
D. `7 xx 10^(8)`

Answer

To find the number of iron (Fe) atoms in 100 grams of hemoglobin that contains 0.33% Fe, we can follow these steps:

### Step 1: Calculate the mass of iron in hemoglobin
Given that hemoglobin contains 0.33% iron, we can calculate the mass of iron in 100 grams of hemoglobin.

\[ \text{Mass of Fe} = \frac{0.33}{100} \times 100 \text{ g} = 0.33 \text{ g} \]

### Step 2: Calculate the number of moles of iron
Next, we need to calculate the number of moles of iron using its mass and atomic mass. The atomic mass of iron (Fe) is given as 56 g/mol.

\[ \text{Number of moles of Fe} = \frac{\text{Mass of Fe}}{\text{Atomic mass of Fe}} = \frac{0.33 \text{ g}}{56 \text{ g/mol}} \approx 0.00589 \text{ mol} \]

### Step 3: Calculate the number of iron atoms
To find the number of atoms, we use Avogadro's number, which is approximately \(6.022 \times 10^{23}\) atoms/mol.

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

\[ \text{Number of Fe atoms} = 0.00589 \text{ mol} \times 6.022 \times 10^{23} \text{ atoms/mol} \approx 3.54 \times 10^{21} \text{ atoms} \]

### Final Result
The number of iron atoms in 100 grams of hemoglobin is approximately \(3.54 \times 10^{21}\) atoms.

---