Radioactivity

Concept 1: What are Isotopes?

• The atomic number, Z, is the number of protons inside the nucleus. It is this number that determines which element it is.

• The mass number, A, is the number of nucleons (protons + neutrons) in the nucleus.

• Isotopes are atoms with the same number of protons but that have a different number of neutrons. Since the atomic number is equal to the number of protons and the atomic mass is the sum of protons and neutrons, we can also say that isotopes are elements with the same atomic number but different mass numbers.

• For example, Hydrogen, Deuterium and Tritium are three isotopes of the element hydrogen with one proton but 0, 1, 2 neutrons respectively.

• For example, carbon-12, carbon-13 and carbon-14 are three isotopes of the element carbon with mass numbers 12, 13 and 14 respectively.

Concept 3: Types of Radioactivity

• Alpha particle emission: A Helium nucleus is emitted with about 10% light speed.  

• Beta particle emission: An electron is emitted with about 90% light speed.

• Gamma rays: High frequency electromagnetic waves are emitted at speed of light.

Application: 

• Discussion the basics of the safe transport of radioactive material (YouTube 8:18, IAEA Nuclear Safety and Security)

Concept 6: Electromagnetic vs. Nuclear Radiation (TED-Ed)

• "Nothing in life is to be feared, it is only to be understood. Now is the time to understand, so that we may fear less." (Marie Curie) 

• Visit the TED-Ed lesson to clarify your fear about the Radiation!