Question

Lodine-131 is a very useful radioactive isotope that is used to locate and treat

cancerous tumors in the body and has a half life of 8 days. If a radiologist
were to use 64 mg of this isotope, how much of it would still be left after 32
days?

Explain what you did to arrive at that answer. If you used an equation, be sure to explain why you used each number in your math equation

Answer 1

y= 4

Explanation:

Answer 2

Explanation:

y = y₀(0.5)^(x/8)

y = current mass

y₀ = original mass = 64 mg

0.5 represents half life

x = number of days since y₀ was presented

1/8 = because it takes 8 days to make 1 half life

y = 64(0.5)^(32/8)

y = 64(0.5)⁴

y = 4 mg