Which of the following are true with regard to isotopes of a given element?

They have the same number of nucleons

They have the same atomic mass

They differ in densities

They have the same number of protons but a different number of electrons

They have the same position on the periodic table

Which of the following statements are correct, when referring to an atom?

The valence shell is responsible for radioactivity

Radioactivity results from an imbalance in the number of protons and electrons

All atoms have an equal number of protons and neutrons

Neutrons have a negative charge

Radon contributes to our background radiation

The production of radionuclides can involve:

The addition of a neutron into a stable nucleus

Capturing a negative electron from the K-shell (electron capture)

Addition of a proton into the nucleus using a nuclear reactor

The use of a cyclotron

Removal of electrons from the inner shell

Concerning radionuclide production:

Radionuclides used in medicine are generally found naturally

In a cyclotron, protons are forced into the nucleus

In a nuclear reactor, the addition of a neutron into the nucleus results in an increase in atomic number

Radionuclides produced in a cyclotron can be separated from the stable (carrier) element

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