Radiation Safety Practice Exam

What charge does an alpha particle carry?

1. +1 (positive one) charge

2. 0 (neutral) charge

3. -1 (negative one) charge

4. +2 (positive two) charge

The correct answer is: +2 (positive two) charge

An alpha particle is composed of two protons and two neutrons, which makes its overall charge +2. This is because protons carry a positive charge, while neutrons are neutral and do not contribute to the overall charge of the particle. Since an alpha particle contains two positively charged protons, it is characterized by a +2 charge, making it a unique particle in terms of its interaction with other matter due to its charge and mass. Understanding that alpha particles are emitted from certain types of radioactive decay is essential, as their charge and mass influence their behavior when interacting with surrounding materials. They are relatively large and carry a positive charge, which means they can cause ionization and affect nearby atoms when they pass through matter. This is also why they tend to have limited penetrating power compared to other types of radiation such as beta particles, which have a different charge and mass.