Question

Calculate the average binding energy per nucleon for Thallium, (atomic mass = 204.974401 u). Answer in MeV plz. Need it asap

Answer 1

The formula for binding energy of an atom is

B.E = Δm × 931 MeV/amu

here Δm is the mass difference between its atomic mass and mass of its nucleons.

In this case, Thallium, 205 Tl has 81 protons and 124 neutrons.

So, this gives it a mass of

nucleon mass = (81 × 1.0073 amu) + (124 × 1.0087 amu) = 206.6701 amu

Therefore, the masss defect of Thallium, 205 Tl is

Δm = 206.6701 amu − 204.974401 amu = 1.695699 amu

So,

B.E = 1.695699 amu × 931 MeV/amu = 1.57869577 × 109 eV

For average binding energy per nucleon,

divide the binding energy by the total number of nucleons, 205.

binding energy per nucleon = 1.57869577 × 109 eV ÷ 205 nucleons

= 7.70 MeV