Question #f10be

1 Answer
Apr 14, 2014

The binding energy is the energy required to break a nucleus into its component nucleons.

For example,

#""_29^63"Cu"# + energy = 29#""_1^1"H"# + 34#""_0^1"n"#

Example:

Find the binding energy of a copper-63 nucleus if its actual mass is 62.9296 u.

We first determine the mass defect, the difference between the mass of a nucleus and the sum of the masses of its nucleons.

Mass of 29 protons = 29 × 1.0073 u = 29.2117 u
Mass of 34 neutrons = 34 × 1.0087 u = 34.2958 u

Total mass of particles = 63.5075 u
Mass of copper-63 = 62.9296 u

Mass defect = 0.5779 u

The mass defect is the binding energy expressed in atomic mass units (u).

Now convert the mass defect into energy.

#E = mc²# = 0.5779 u × #(1.6605 × 10^(-27)" kg")/(1" u") × (2.9979 ×10^8" m·s⁻²")^2# = 8.648 × 10⁻¹¹ J

This is the binding energy per nucleus.

The binding energy per mole is 6.0221 × 10²³ × 8.648 ×10⁻¹¹ J =
5.207 × 10¹³ J/mol = 52.07 TJ/mol