- Phenomenon of radioactivity was first discovered by A.H.Bacquerel in 1896 while studying fluorescence and phosphorence of compounds irradiated by visible light
- these phosphorescent materials glow in dark after being exposed to visible light
- while conducting experiment on uranium salts, he found that uranium salts has a capability to blacken the photographic plate kept in a dark place wrapped through a paper
- Subsequent experiments showed that radioactivity is a nuclear phenomenon in which an unstable nucleus under goes a decay process referred as radioactive decay
- There are three types of radioactivity decays that occur in nature .These are α decay ,β decay and γ decay.
- We now define radioactive decay as the process by which unstable atomic nucleus looses energy by emitting ionizing particles or radiations ( α,β and γ rays)
- Radioactive decay of an atomic nucleus is a spontaneous process and can occur without any interaction of other particles outside the atom
- This process of radioactive decay is random and we can not predict whether a given radioactive atom will emit radiations at a particular instant of time or not
- Phenomenon of radioactivity is observed in heavy elements like uranium and unstable isotopes like carbon 14
Introduction to radioactivity
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