AP Physics B Chapter 30 Nuclear Chemistry30-1 Structure and Properties of the Nucleus

*Mp = 1.6726 x 10 -27 kg*Mn = 1.6749 x 10 -27 kg*These are called nucleons.*The number of protons in the nucleus is the atomic number….Z*The number of protons plus neutrons …..A*Isotopes of an atom have the same number of protons but different numbers of neutrons.*We use the isotope mass with the natural abundance to calculate the atomic mass of an atom.

30-1 cont’d

• D=2r=(1.2x 10 -15 m) (A 1/3 )• *See Example 30-1

30-2 Binding Energy and Nuclear Forces

• See Example 30-2• *The total binding energy of the nucleus

represents the amount of energy that must be put into a nucleus in order to break it apart into its protons and neutrons.

• The average binding energy per nucleon is defined as the total binding energy divided by A.

• See Example 30-3 30-4

• The strong nuclear force is an attractive force that acts between all nucleons- protons and neutrons.

• It is a short-range force• Electrical and gravitational forces are long-

range forces.• See p 921 for band of stability.

30-3 Radioactivity

• Henri Becquerel (1852-1908)• Marie Curie 1867-1934)• Pierre Curie (1859-1906)

30-4Alpha Decay

See p 923

30-5 Beta Decay

30-6 Gamma Decay

HW TXT30A

• Page 940 1-4,6,10-12,19-22,28 due Wed BOP