Strontium-90 Is a Byproduct in Nuclear Reactors Fuelled by the Radioisotope

question 21

Multiple Choice

Strontium-90 is a byproduct in nuclear reactors fuelled by the radioisotope uranium-235. The half-life of strontium-90 is 28.8 y. What percentage of a strontium-90 sample remains after 85.0 y.?

• A) 33.9%
• B) 2.95%
• C) 87.1%
• D) 0.129%
• E) 12.9%

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