Question

If the initial amount of strontium-90 is 4.0g, and its half-life is 25 years, how much strontium-90 will remain after 100 years?

A) 0.25g
B) 0.50g
C) 1.00g
D) 2.00g

Answer 1

The amount of strontium-90 remaining after 100 years is 0.25g.

Step-by-step explanation:

To calculate the amount of strontium-90 remaining after a certain time, we can use the exponential decay formula:

N(t) = N0 * (1/2)^(t/T)

Where:

• N(t) is the amount remaining after time t
• N0 is the initial amount
• t is the time elapsed
• T is the half-life

In this case, the initial amount of strontium-90 is 4.0g, the time elapsed is 100 years, and the half-life is 25 years. Plugging these values into the formula, we get:

N(t) = 4.0g * (1/2)^(100/25) = 4.0g * (1/2)^4 = 4.0g * 1/16 = 0.25g

Therefore, 0.25g of strontium-90 will remain after 100 years.