Question

QUESTION 9

7. A single pill, Isotope of Iodine \({ }^{131}\) I produces \(9.6 \times 10^{14}\) iodine, \({ }^{131} \mathrm{I}\) atom, and it has a halflife of 8 days. How many of \(^{131}\) I the atoms remain, as multiple of \(10^{7}\), after 200 days from production of the pill?

QUESTION 10

1) A electron is confined in one dimensional atomic box of length, where \(L=5^{*} 10^{-10}\) meters. The energy levels are set as energies of particle in the box. \(\left(m_{e}=9.1 \times 10^{-31} \mathrm{~kg}, h=6.63 \times 10^{-34} \mathrm{~J} \cdot \mathrm{s}\right.\), 1E.V \(=1.6 \cdot 10^{-19}\) Joules)

What is the ground state \((n=1\), the first energy state) of this electron in electron volt in two significant figure, or one decimal unit?(Hint: solve the energy in joules and convert to electron volt.)

Answer 1

ANSWER

Q. 9. Initial Noi af atoms = 9.6 x 1014 Half life Typ - 8 days, Time duration t' a 200 days. Decay contant aa 0.693 – 0.693 Using N= No ett No zent - logo) = 2t 0693 x 200 = 17.325 2.303 x los Mo) a 17.325 17.325 2.303 = 7.523. dog No-log N = 7.523. log N = log No - 7.523 a log (9.6x1014) -7.523. = logg.6 + 16 log10 -7.523. = 0.9823 + 14 - 7.523 = 14.9823 – 7.523 = 7.4593. Antiloganthes on both sides N: 28790000 22.879 x 10? Taking - No of atoms after 200 days = d.879 x 10?