After 1.96 days, the activity of a sample of an unknown type radioactive material has decreased to 91.2% of the initial activity. What is the half-life of this material?
After 1.96 days, the activity of a sample of an unknown type radioactive material has decreased...
A 50.0 mg sample of an unknown radioactive substance was placed in storage and its mass measured periodically. After 70.9 days70.9 days, the amount of radioactive substance had decreased to 3.13 mg. What is the half-life of the unknown radioactive substance? half-life: days
A sample of radioactive material is initially found to have an activity of 114 Bq. After 4 days and 5 hours, the activity of the sample is found to be 85 Bq. 1) Calculate the disintegration constant of this material. 1 = 51 Submit 2) Calculate the half-life of the material. T12- days Submit 3) How long from the beginning (when the activity was 114 Bq) did it take for the sample to reach an activity of 10 Bq? t...
A 175 ng sample of radioactive material has a half life of 8.8 days. How many ng of radioactive material is left after 3 half lives? Do not put units in your answer
91. If the half – life of a sample of radioactive material is 60 days, what fraction of the original radioactive nuclei will remain after 120 days.
A radioactive substance with a half-life of 3.0 days has an initial activity of 2400 Bq. What is its activity after 6.0 days?
A sample of radioactive material is initially found to have an activity of 115 decays/min. After 4 d 22 h, its activity is measured to be 63 decays/min. 1) (a) Calculate the half-life of the material.
A sample of radioactive material contains 1.1E15 atoms and has an activity of 6.3E11 Bq. What is its half-life? A sample of radioactive material contains 1.1 x 1015 atoms and has an activity of 6.3 x 1011 Bq. What is its half-life? 1.16E3 X Your response is within 10% of the correct value. This may be due to roundoff error, or you could have a mistake in your calculation. Carry out all intermediate results to at least four-digit accuracy to...
a radioactive material has a half life of 7 days. how many radioactive isotopes are left after 33 hours, if you had 7000000 isotopes in the beginning? Question 33 1 pts A radioactive material has a half life of 7 days. How many radioactive isotopes are left after 33 hours, if you had 7 000 000 isotopes in the beginning? Use 2 sig figs in your answer. < Previous Next >
You have an unknown radioactive material. If you start out with a 405 mg sample, and after 120 minutes, 53.1 mg remains, what is the half life?
A sample of a certain radioactive substance is prepared, and its initial activity is 4 µCi. After 2.4 hours, the activity is measured to be 1 µCi. What is the half-life of this material?