Chemistry

posted by .

Will you check this answer for me?
the half-life of strontium-87 is 2.8hr. What percentage of this isotope will remain after 8 hours and 24 minutes?

?? 34%

  • Chemistry -

    I'd be interested in knowing how you came up with that answer.
    8 hr and 24 min, according to my calculation is [(8*60)+24/60] = 8.4 hrs.
    k = 0.693/t1/2 = 0.693/2.8 = 0.2475
    ln(No/N) = kt
    I took No = 100 (an arbitrary number)
    Solved for N
    k from above
    t = 8.4
    Solving for N, I obtained 12.5 so if we started with 100 g at time = zero, then at the end of 8.4 hours we would have 12.5 g left. %left = (12.5/100)*100 = ??
    Check my work.

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. Chemistry

    Which radioactive sample would contain the greatest remaining mass of the radioactive isotope after 10 years?
  2. Physcis 30

    Q1) If there are 100 radioactive atoms with a half-life of 30 seconds, how many radioactive atoms will remain after one half-life (30 seconds)?
  3. Chemistry

    I've figured out most of it. I'm not sure how to find the percentage ofd the isotope. Define the half life. The half-life of a radioisotope is found to be 4.55 minutes. If the decay follows first order kinetics, what percentage of …
  4. physics

    The half-life of a certain radioactive isotope is 32 hours.What fraction of the sample would remain after 16 hours?
  5. College Algebra

    Use a calculator to help solve the problem. One isotope of holmium, 162Ho, has a half life of 22 minutes. The half-life of a second isotope, 164Ho, is 37 minutes. Starting with a sample containing equal amounts, find the ratio of the …
  6. Half-life

    After two hours, 1/16 of the initial amount of a radioactive isotope remains undecayed. What is the half-life of the isotope?
  7. Chemistry

    The strontium-90 isotope decays by the reaction below. It has a half-life of 28 yr. If the initial activity of this isotope was 168dpm, what would the activity be after 28.0 yr?
  8. chemistry

    the half time of a radioisotope is found to be 4.55 minutes. if the decay follow first order kinetics. what percentage of isotope will remain after 2.00 hours?
  9. Math

    The element strontium-90 is radioactive. The percent of strontium -90, A(t), left in a sample can be modelled by the half-life function A(t) = A0 (1/2)^t/29, where t represents the time, in years, after the initial time, and A0 represents …
  10. math

    Suppose strontium-90 decays at a rate of 2 percent per year. (a) Write the fraction P of strontium remaining, as function of t, measured in years. (Assume that at time t=0 there is 100 % remaining.) Answer: P(t)=(.98)^t (b) Estimate …

More Similar Questions