Question

Question 8 of 15

The half-life of radium-226 is 1,600 years. It decays into radon-222. What
fraction of the original amount of radium-226 in a sample will still be radium
after 8,000 years?
C.
D.
SUBMIT

Answer 1

To find the fraction of the original amount of radium-226 that will still be radium after 8,000 years, we can use the formula for radioactive decay:

Fraction remaining = (1/2)^(t/half-life)

Where:

t is the time in years.
half-life is the half-life of the substance.
In this case, the half-life of radium-226 is 1,600 years, and you want to find the fraction remaining after 8,000 years. Plugging these values into the formula:

Fraction remaining = (1/2)^(8000/1600)

Fraction remaining = (1/2)^5

Fraction remaining = 1/32

So, after 8,000 years, 1/32 of the original amount of radium-226 will still be radium. Therefore, the answer is C.