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    I don't understand how to calculate the answer to this question: The half-life of one radioactive isotope is 71 days. By starting with 16g, calculate the mass of the remains that are left of this isotope after 213 days.
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    (Original post by Tayla1998)
    I don't understand how to calculate the answer to this question: The half-life of one radioactive isotope is 71 days. By starting with 16g, calculate the mass of the remains that are left of this isotope after 213 days.
    doesn't this mean every 71 days 1 half-life is completed i.e. the mass of the radioactive isotope is halved?
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    (Original post by Tayla1998)
    I don't understand how to calculate the answer to this question: The half-life of one radioactive isotope is 71 days. By starting with 16g, calculate the mass of the remains that are left of this isotope after 213 days.
    Three half lives have passed after 213 days (213/71 = 3)

    After one half life 8g remains
    After two half lives 4g remains
    After three half lives 2g remains
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    (Original post by charco)
    Three half lives have passed after 213 days (213/71 = 3)

    After one half life 8g remains
    After two half lives 4g remains
    After three half lives 2g remains
    Thanks for your help.
 
 
 
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