Answer:
a. 80 g ⟶ 40 g ⟶ 20 g ⟶ 10 g ⟶ 5 g …
b. 0 da ⟶ 8 da ⟶ 16 da ⟶ 24 da ⟶ 32 da …
c. 8 da
Explanation:
Assume that the decay curve looks like the first one below.
a. Mass of I
The mass of iodine decreases by half after each half-life.
Thus, the masses decrease in the sequence
80 g ⟶ 40 g ⟶ 20 g ⟶ 10 g ⟶ 5 g …
b. Time
The horizontal axis has repeating units every 8 da.
Thus, the time increases in the sequence
0 da ⟶ 8 da ⟶ 16 da ⟶ 24 da ⟶ 32 da …
The completed graph is the second one below.
c. Half-life
It takes 8 da for 80 g of iodine to decrease to 40 g.
The half-life of iodine is 8 da.
