Table of Contents
- 1 How do you calculate the half-life of a radioactive source?
- 2 What is the half-life of the radioactive isotope in hours?
- 3 What is the half-life for your isotope?
- 4 How is radioactivity concentration calculated?
- 5 What is meant by the half-life of a radioactive isotope quizlet?
- 6 What element has a half-life of 4 days?
- 7 How many atoms are left after 4 half-lives?
- 8 What is the half-life of carbon-10?
- 9 What is the half life of uranium-233?
How do you calculate the half-life of a radioactive source?
A number of measurements are made and an average value is calculated. The average value is the half-life of the radioactive source. The graph above shows the activity of a radioactive source over a period of time….Measuring half-life.
| Time (hours) | Corrected count rate (counts per minute) |
|---|---|
| 4 | 20 |
| 5 | 13 |
What is the half-life of the radioactive isotope in hours?
Half-lives of isotopes commonly used in GCSE questions
| Isotope | Half-life |
|---|---|
| Caesium-137 | 30 years |
| Cobalt-60 | 5.27 years |
| Polonium-210 | 138 days |
| Technetium-99m | 6 hours |
What is the half-life for your isotope?
one-half
The half-life of a radioactive isotope is the amount of time it takes for one-half of the radioactive isotope to decay. The half-life of a specific radioactive isotope is constant; it is unaffected by conditions and is independent of the initial amount of that isotope.
Which radioactive isotope has the longest half-life?
Bismuth-209
Bismuth-209 (209Bi) is the isotope of bismuth with the longest known half-life of any radioisotope that undergoes α-decay (alpha decay). It has 83 protons and a magic number of 126 neutrons, and an atomic mass of 208.9803987 amu (atomic mass units).
How does half-life relate to radioactive decay?
The decay of radioactive elements occurs at a fixed rate. The half-life of a radioisotope is the time required for one half of the amount of unstable material to degrade into a more stable material. After ten half-lives, less than one-thousandth of the original activity will remain.
How is radioactivity concentration calculated?
Enter the specific radioactivity as cpm/fmol, the number of cpm counted, and the volume counted. The result is the concentration in nM. Divide cpm by cpm/fmol to get the number of fmols. Divide by volume.
What is meant by the half-life of a radioactive isotope quizlet?
Half life is the time it takes for the number of nuclei in a radioactive isotope in a sample to halve.
What element has a half-life of 4 days?
Radon-222
Radon-222, for example, has a half-life of just four days.
What is an atom half-life?
half-life, in radioactivity, the interval of time required for one-half of the atomic nuclei of a radioactive sample to decay (change spontaneously into other nuclear species by emitting particles and energy), or, equivalently, the time interval required for the number of disintegrations per second of a radioactive …
What is the half life of a radioactive isotope?
Each radioactive element has a different half life decay time. The half-life of carbon-10, for example, is only 19 seconds, so it is impossible to find this isotope in nature. Uranium-233 has a half-life of about 160000 years, on the other hand.
How many atoms are left after 4 half-lives?
6) atoms remaining after 4 half-lives: (66858 atoms) (0.0625) = 4179 atoms (to the nearest whole number) Problem #30:The isotope Ra-226 decays to Pb-206 in a number of stages which have a combined half-life of 1640 years.
What is the half-life of carbon-10?
The half-life of carbon-10, for example, is only 19 seconds, so it is impossible to find this isotope in nature. Uranium-233 has a half-life of about 160000 years, on the other hand. This shows the variation in the half-life of different elements. The concept if half-life can also be used to characterize some exponential decay.
What is the half life of uranium-233?
Half-life is defined as the time needed to undergo its decay process for half of the unstable nuclei. Each radioactive element has a different half life decay time. The half-life of carbon-10, for example, is only 19 seconds, so it is impossible to find this isotope in nature. Uranium-233 has a half-life of about 160000 years, on the other hand.