Question

The half-life of iodine-131 is 8 days. Chan Hee examines two samples of iodine-131. Sample 1: 10 g Sample 2: 20 g What can Chan Hee expect to observe about the samples after 16 days?
a. The mass of iodine-131 in sample 1 will be 7.5 g and in sample 2 will be 16 g.
b. Three-fourths of each sample will have undergone radioactive decay.
c. Ten grams of each sample will have undergone radioactive decay.
d. One-half of each sample will still be iodine-131.

Answer 1

Chan Hee can expect to observe about the samples after 16 days is that three-fourths of each sample will have undergone radioactive decay. The best answer is letter B.