Question

Define isodiapheres and give 2 examples?

Answer 1

Isodiaphers are sets of nuclides which may have different numbers of protons or neutrons, but have the same difference between the number of protons and neutrons i.e. neutron excess.

For example Thorium-234 and Uranium-238 are isodiaphers.

For Thorium-234, number of protons = 90, number of neutrons =144, hence neutron excess is 54

For Uranium-238, number of protons = 92, number of neutrons = 146, hence neutron excess is again 54.