Answer to Question #147670 in Organic Chemistry for Zainab

Question

calculate the binding energy per atoms, per nucleon, and per mole for a maganese-55 atom measured mass 54.938047 u

Answer 1

Binding energy = Mass defect × c²

Mass defect = mass of the element - observed mass

Mass defect = (25×1.00728 + 30×1.00867) - 54.938047 =

0.504053 amu

Converting the mass from kg to amu,

0.504053 amu = 0.504053 × 1.66×10-²⁷ kg = 8.367 × 10-²⁸kg

E = mc² = 8.367 × 10-²⁸ × (3 × 10⁸)² = 7.53×10-¹¹J per atom

= 7.53×10-¹⁴lkj/atom

To convert to kj/mol, we multiply the energy by the number of atoms in a mole;

E = 7.53×10-¹⁴ × Avogadro's number

E = 7.53×10-¹⁴ × 6.02 × 10²³ =

4.53 × 10¹⁰kj/mole