Question

Which of the following situations indicates an alpha emission?

The atomic number increases by one, but the mass number does not change.


The atomic number decreases by one,and the mass number decreases by one.


The atomic number decreases by two, and the mass number decreases by four.


The atomic number and the mass number both decrease by two.

Answer 1

Your answer would be C. Alpha decay involves the ejection of 2 protons and 2 neutrons from the nucleus for a total of 4 amu lost. This form of decay is most common in heavy elements.