The half-life for a 100-gram sample of radioactive element X is 5 days. How much of element X remains after 10 days have passed?

a
25 g
b
75 g
c
100 g
d
50 g

1 answer

The half-life of element X is 5 days, which means that every 5 days, the amount of element X will be reduced by half.

After 5 days, there will be 50 grams of element X remaining (half of the original 100 grams).

After another 5 days (10 days total), the remaining 50 grams will be reduced by half again, leaving 25 grams of element X remaining.

Therefore, the answer is 25 grams.

The correct option is a) 25 g.