Chemistry

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A radioactive element has a half-life of 6.41 days. What percent of the original sample will be left after 15.0 days?

  • Chemistry -

    estimate: that is over 2 half lives, guessing 20 percent. The math

    amountremaining=original*e^(-ln2*15/6.42)

    decimal percent=e^(-ln2*15/6.42)=.199
    or 19.9 percent

  • Chemistry -

    Thanks

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