Question

The half-life of a strontium isotope is 25 years. How much of this particular isotope will remain after 100 years if the starting mass is 16 grams?

Answer 1

1 gram

Step-by-step explanation:

Half life = 25 years

Starting mass = 16 grams

Time = 100 years

Number of half lives = Time / Duration of Half life = 100 / 25 = 4

After first Half life;

Remaining mass = 16 / 2 = 8 g

After Second Half life;

Remaining mass = 8 / 2 = 4 g

After Third Half life;

Remaining mass = 4 / 2 = 2 g

After Fourth Half life;

Remaining mass = 2 / 2 = 1 g