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2007-01-30 23:08:52 · 0 answers · asked by Mr.McLaren 2 in Science & Mathematics Chemistry

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The most radioactive element is Polonium

Polonium is a very rare natural element. Uranium ores contain only about 100 micrograms of the element per ton. Its abundance is only about 0.2% of that of radium.

In 1934, scientists discovered that when they bombarded natural bismuth (209Bi) with neutrons, 210Bi, the parent of polonium, was obtained. Milligram amounts of polonium may now be prepared this way, by using the high neutron fluxes of nuclear reactors.

Polonium-210 is a low-melting, fairly volatile metal, 50% of which is vaporized in air in 45 hours at 55?C. It is an alpha emitter with a half-life of 138.39 days. A milligram emits as many alpha particles as 5 g of radium. The energy released by its decay is so large (140W/g) that a capsule containing about half a gram reaches a temperature above 500C. The capsule also presents a contact gamma-ray dose rate of 0.012 Gy/h. A few curies (1 curie = 3.7 x 1010Bq) of polonium exhibit a blue glow, caused by excitation of the surrounding gas.
So it's much more dangerous than Radium, that is itself one of the most radioactive elements.

2007-01-30 23:44:02 · answer #1 · answered by scientific_boy3434 5 · 1 2

Most Radioactive Element

2016-10-28 20:39:44 · answer #2 · answered by witek 4 · 0 0

i think both cesium and francium

2007-01-30 23:14:35 · answer #3 · answered by rawand m 2 · 0 6

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