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The half life of uranium 235 is 700 million years After 1.4 billion or 1 400 million years what fraction of the original amount of uranium 235 remains?
Wiki User
∙ 13y ago
A half life pertains to the time it takes for exactly half of a substance to disappear. So, if U235 has a half life of 700 million years, it will take 700 million years for half of it to decay. That would leave .5kg or 500g.
Wiki User
∙ 14y ago
Wiki User
∙ 14y agoUranium 235, with a half-life of 700 million years1, will decay to 0.95x10-6 of its original value after 14 billion years, and to 0.25 of its original value after 1400 million years.
AT = A0 2(-T/H)
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1The actual half-life of 235U92 is 704 million years. The answer given used 700, not 704.
Wiki User
∙ 14y agoSince that is exactly 2 times the half-life, 1/4 (that is, 1/2 x 1/2) of the original amount will be left.
Wiki User
∙ 13y ago50 % from the initial quantity
Wiki User
∙ 7y agoThe half-life is 700 million years !
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