Answer :
Final answer:
After one half-life of 6 hours, half of the initial 0.179 mol of a radioactive sample would remain, resulting in 0.0895 mol. After two half-lives (12 hours), this would further reduce to 0.04475 mol. After nine half-lives (36 hours), approximately 0.0028 mol would remain.
Explanation:
The question asks about the remaining amount of radioactive nuclei after a given period, specifically after one, two, and nine half-lives. In the case of a radioactive sample with an initial amount of 0.179 mol and a half-life of 6 hours, after one half-life (6 hours), the amount of radioactive material remaining would be half of the initial amount.
Thus, after 6 hours:
- 0.179 mol / 2 = 0.0895 mol remain
After 12 hours (two half-lives):
- 0.0895 mol / 2 = 0.04475 mol remain
And after 36 hours (six half-lives):
- 0.179 mol / 26 = 0.179 mol / 64 ≈ 0.0028 mol remain
