How to find
binding energy per nucleon
Before we start to calculate the binding
energy of nuclei, let us look into what binding energy is all about.
Binding energy is the energy needed
to hold the aggregate number of protons and neutrons together n a
nucleus of an atom, he energy required to split a given nucleus into its
constituent protons and neutrons is the binding energy of that nuclei.
In a nucleus
of all atoms (except hydrogen with only proton) there are protons and neutrons,
theses protons and neutrons are called the nucleons. When we talk of binding
energy per nucleon, we refer to the total binding energy of an atom divided by
the number of protons and neutrons which equal to the atomic mass of the atom.
Therefore to find the binding energy per nucleon of any atom or nucleus we
first calculate the total binding energy of the atom, and then divide it by the
atomic mass of the atom.
How To Calculate The Actual Mass
To calculate the binding energy per nucleon of
an atom we subtract the measured atomic mass of the said atom from the actual atomic mass and use the Einstein mass energy relation
of e =mc2 to calculate the binding energy.
The measured atomic mass is the mass obtained
from the atoms are actually measured, this mass are mostly available in periodic table of element as a
scientific standard, the actual mass is
the mass obtained when the individual
mass of the protons and neutrons in an atom are calculated.
To obtain the actual mass for any atom we can
use the formula below.
P(1.007825) + N(1.008665)= actual mass.
Where P is the number of protons and N is the
number of neutrons.
To find
the number of neutrons
we subtract the atomic mass from the atomic
number
N= A-Z
where A is the atomic mass and Z is the atomic
number or number of protons.
After
obtaining our measured mass and actual mass we can find the mass defects, mass
defects is the difference between the measured mass and the actual mass.
Calculating The Binding Energy
let MP be the mass of proton and MN be the mass of
neutron
Z is the
atomic number and A is the atomic mass.
the mass defect will therefore be
∆M= Z MP + (A-Z) MN
To calculate the binding energy we use the Einstein
mass energy relation,
E =MC2
E is the
energy in evolt, and is the speed of
light, given as 3x 108 m/s
E =∆MC2
B =∆MC2
To obtain
the binding energy per nucleon we divide value B with A,
i.e B/A is the binding energy per nucleon.
the average
binding energy is 8.4MeV for must nucleis.
No comments:
Post a Comment