algebra

posted by .

Suppose a sample of Cesium-137 with initial mass of 200 grams decays to a mass of 160 grams voer the course of 10 years.
Find the half-life of Cesium-137 (Round to the nearest year)
How much Cesium-137 is left in the sample after 60 years? Round to the nearest tenth of a gram.

  • algebra -

    If T is the half life,

    (1/2)^(t/T) = 0.16/0.20 = 0.80
    where t = 10 yr

    (t/T) = 0.3219
    T = 31 yr

    After 60 yr, the fraction left is
    (0.5)^(60/31) = 0.261

    Amount left = 200*0.261 = 52.3 g

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. word problem

    The half life of cesium-137 is 30 years. Suppose we have a 10-g sample. a)Find a function that models the mass remaining after t years. b)How much of the sample will remain after 80 years?
  2. Chemistry please help!

    A Cesium 137 sample has a measured radioactivity of 50 microcuries.Cesium 137 has a half-life of 30 years. How long will it take this sample to be reduced to a residual radioactivity of 6.25 microcuries?
  3. Chemistry/math

    Cesium-137 has a half-life of 30 years. Suppose a lab stored a 30-mCi sample n 1973. How much will be left in 2063?
  4. Nuclear Physics

    An investigator receives Co-60 (5.27 year half life) for use in a research study. Unfortunately the Co-60 is contaminated with Cs-137 (30.0 year half life). The initial Co-60 activity is 400 times the initial Cs-137 activity. How long …
  5. chem

    Cesium-137 has a half life of 30.0 years. If initially there are 8.0 kg of cesium-137 present in a sample, how many kg will remain after 60.0 years?
  6. Calculuc

    How do you set up this problem? The decay constant for the radioactive element cesium 137 is .023 when time is measured in years. Find its half-life.
  7. math

    how much cesium-137 would remain after 120.0 years if you started with 34.0 grams
  8. math

    5. Cesium-137 is a radioactive isotope. The following formula represents the remaining amount of a 300 gram sample of cesium-137 in a storage tank after t years: N(t)=300e−0.02297t A) Determine the remaining amount of cesium-137 …
  9. Chemistry

    The cesium-131 nuclide has a half life of 30 years. After 90 years, about 6g remain. What is the original mass of the cesium-131 sample?
  10. chem

    Cesium-137 is part of the nuclear waste produced by uranium-235 fission. The half-life of cesium-137 is 30.2 years. How much time is required for the activity of a sample of cesium-137 to fall to 25.1 percent of its original value?

More Similar Questions