Question

Hemoglobin contains 0.34% of iron by mass. The number of Fe atoms in 3.3 g of hemoglobin is ______.

(Given: Atomic mass of Fe is 56 u, N_A in 6.022 × 10²³ mol⁻¹)

Options

• 1.21 × 10⁵

• 12 × 10¹⁶

• 1.21 × 10²⁰

• 3.4 × 10²²

Answer 1

Hemoglobin contains 0.34% of iron by mass. The number of Fe atoms in 3.3 g of hemoglobin is 1.21 × 10²⁰.

Explanation:

No. of Fe atoms in 3.3 g of hemoglobin

= `0.34/100 xx 3.3/56 xx 6.022 xx 10^23`

= 1.206 × 10²⁰