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2.Uranium-235 has a half-life of about 700 million years. If 1 kg of U-235 is put on a shelf in

a laboratory, how much of it will be left after 700 million years? (5 points)

User KwiZ
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1 Answer

6 votes

Answer:

.5 kg

Step-by-step explanation:

At the start of Uranium-235 there is a total of 1 kg. Uranium-235 half life is 700 million years, take 1kg ÷2 = 0.5kg after 1 half life.

Let's say another 700 million years go by that means you take 0.5kg and divide that by 2.

0.5kg÷2= 0.25 kg is left after 2 half lives.

Hope this helps good luck!

User Jiayu Zhang
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