The document discusses the discoveries of Marie and Pierre Curie in the late 1800s. They discovered the radioactive elements polonium and radium. Polonium is a silvery radioactive substance that was studied for heating spacecraft but found to be too unstable. Radium is pure white but oxidizes black over time, and has a half-life of 1601 years as it decays into radon gas. The passage also mentions that life is not easy for any of us, but we must believe we are talented at something and do everything possible to achieve it.
53. Po - Polonium Polonium is a silvery substance which is radioactive. Polonium has been studied for some use of heating spacecraft. However polonium is highly unstable and will not be used for such heating methods. Ra - Radium Radium is pure white however it oxidizes in the air and turns black. It has a half-life of 1601 years and decays into radon gas!!
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55. „Az élet egyikünk számára sem könnyű…de hinni kell, hogy van tehetségünk valamihez és hogy ehhez a valamihez mindenáron el kelljutnunk.
