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What is Radioactivity? Radioactivity is the spontaneous breaking up of a certain unstable nuclei accompanied by the emission of radiation.
Who discovered Radioactivity? Henri Becquerel, a French Scientist.
How did he discover radioactivity? He did this by exposing crystals of uranium of sunlight on a photographic plate. An image resulted on the photographic plate. He thought the energy from the sun was released.
What are alpha particles? Alpha particles are helium nuclei He(2)(4) with a positive charge with a little penetrating ability,can be stopped by a piece of paper.
What are Beta particles? They are electrons with a negative charge (-) and are greater penetrating ability. Can be stopped by 5mm Alliminium.
Created by: Elif07