Answer: Given information:
The half-life of a certain radioactive isotope is 50 years.
1. What is the half-life of this isotope?
The answer is straightforward: the half-life is 50 years.
2. What is the mass of the radioactive isotope at 2.0 half-lives?
After 1 half-life, the mass of the isotope will be half of the initial mass. After 2 half-lives, the mass will be half of the remaining mass, which is one-quarter of the initial mass.
Let's assume the initial mass is 100 units (it can be any value, but 100 makes the calculation easy). After 1 half-life, the mass will be 50 units. After 2 half-lives, the mass will be 25 units.
So, the mass of the radioactive isotope at 2.0 half-lives is 25 units.
3. How many half-lives occurred during the first 100 years?
Since the half-life is 50 years, we can divide 100 years by 50 years to find the number of half-lives:
100 years ÷ 50 years/half-life = 2 half-lives
Therefore, 2 half-lives occurred during the first 100 years.
Explanation:
Answer:
1. 25 years
2. 25 grams
3. 4 half lives
Explanation:
The half life of an isotope is the amount of time it takes for half of its mass to decay.
1. Initially, the mass of the isotope is 100 grams. After one half life has passed, the mass will be halved to 50 grams. According to the graph, this happens after 25 years. So the half life of this isotope is 25 years.
2. Two half lives is 50 years. At this time, the mass of the isotope is 25 grams. This makes sense, since after two half lives, the initial 100 grams is halved twice.
3. Since the half life is 25 years, there will be 4 half lives in 100 years.