Half life - Radioactivity Flashcards
What is half life - definition
The interval of time required for one-half of the atomic nuclei of a radioactive sample to decay.
What is an example of half life?
In 5 years 5% radioactivity - In 10 years 2.5% radioactivity ect.
Radio active decay - what are the 3 forms and their definitions?
Alpha decay - when alpha particles are lost from the nucleus, consisting of 2 neutrons and 2 protons - this results in decrease in mass/atomic number.
Beta decay - Beta decay is the ejection of beta particles from a nucleus. Instead, it forms when a neutron is converted into a proton and an electron. Since beta particles contain no protons or neutrons, they have a mass number of 0.
Gamma decay - Gamma decay is the emission of gamma rays from a nucleus. Gamma rays are not particles, but a type of electromagnetic wave, similar to X-rays but having more energy. Gamma radiation results from the movement of protons and neutrons in a high-energy nucleus. Since gamma decay does not change the number of protons or neutrons in a nucleus, the atomic number and mass number stay the same.
