IB Physics 7.2 Key Term Quiz

A nuclei with the same number of protons (Z) but different number of

neutrons (N)

A proton or neutron

 Number of nucleons (protons +

neutrons) in nucleus

Number of protons in nucleus

When an unstable nucleus emits a particle (alpha, beta,

gamma)

a. the time taken for ½ the number of radioactive nuclei in sample to decay

b. the time taken for the activity of a sample to decrease to ½ its initial value

When a nucleus is bombarded in a laboratory with a

nucleon, an alpha particle or another small nucleus, resulting in a nuclide with a

different proton number (a different element).

1/12 th the mass of a carbon-12 nucleus

 Difference between the mass of the nucleus and the sum of the

masses of its individual nucleons

 Energy released when a nuclide is assembled from its

individual components