Nuclear Reactor Engineering: Reactor Systems Engineering, Springer 4th edition, 1994, ISBN: 978-0412985317 Stacey, Nuclear Reactor Physics, John Wiley & Sons, 2001, ISBN: 0- 471-39127-1. Baratta, Introduction to Nuclear Engineering, 3d ed., Prentice-Hall, 2001, ISBN: 8-1. Lamarsh, Introduction to Nuclear Reactor Theory, 2nd ed., Addison-Wesley, Reading, MA (1983). 336,100 US gallons of automotive gasoline.One mole of 63Cu (~63 grams) is bound by the nuclear binding energy (5.3227 x 10 10kJ/mol) which is equivalent to: However, the nuclear binding energy may be expressed as kJ/mol (for better understanding).Ĭalculate the nuclear binding energy of 1 mole of 63Cu: The energy calculated in the previous example is the nuclear binding energy. The mass defect is Δm = 63.50590 u – 62.91367 u = 0.59223 uĬonvert the mass defect into energy ( nuclear binding energy). The mass of a proton is 1.00728 u and a neutron is 1.00867 u. For 63Cu the atomic mass is less than 63 so this must be the dominant factor.Ĭalculate the mass defect of a 63Cu nucleus if the actual mass of 63Cu in its nuclear ground state is 62.91367 u.Ħ3Cu nucleus has 29 protons and also has (63 – 29) 34 neutrons. A nucleus with greater binding energy has a lower total energy, and therefore a lower mass according to Einstein’s mass-energy equivalence relation E = mc 2. The nuclear binding energy varies between nuclei.This increases the mass of nuclei with more neutrons than protons relative to the atomic mass unit scale based on 12C with equal numbers of protons and neutrons.

The neutron is slightly heavier than the proton.

There are two reasons for the difference between mass number and isotopic mass, known as the mass defect: For example, 63Cu (29 protons and 34 neutrons) has a mass number of 63 and an isotopic mass in its nuclear ground state is 62.91367 u. For other isotopes, the isotopic mass usually differs and is usually within 0.1 u of the mass number. One unified atomic mass unit is approximately the mass of one nucleon (either a single proton or neutron) and is numerically equivalent to 1 g/mol.įor 12C the atomic mass is exactly 12u, since the atomic mass unit is defined from it. It is the carbon-12 atom, which, by international agreement, has been assigned a mass of 12 atomic mass units (u). One atomic mass unit is equal to 1.66 x 10 -24 grams.īesides the standard kilogram, it is a second mass standard. The unit of measure for mass is the atomic mass unit (amu). Units of measure have been defined for mass and energy on the atomic scale to make measurements more convenient to express.

The size and mass of atoms are so small that the use of normal measuring units, while possible, is often inconvenient.

Atomic mass unit calculator