Which of the following physical quantities ham2 2(ncu1pz rks the same SI unit as the radioactive decay constanc z1pknr(2u 2mt?

  The diagram below shows the graph of binding energy per nucleon vs. the , pnj5badu.i( mass (nucleon) number of som5 (d,jn ubpai.e elements.

Which is the most stable nucleus?

  A student uses the arrangement shown below to ascertain the typ30 ) aym(nlhlro-q*x1ux+i ubnxf:y ;9rl4ffe of radiation emitted by a given sample of radioactive material. mf-nxulu3i * +ff(y 4a n rxyr)q; ho9:ll01bx

The SI unit of radioactive decay constant is $s^{−1}$, which is the same as that of frequency.When the sheet of paper is in the position shown, a count rate of 720 Bq is recorded. When she lowers the thick sheet of paper so as to obstruct the direct path between the source and the detector, the count rate drops to 18 Bq. Which of the following is the most likely explanation for the data collected?

  The binding energy ofua ula :u47r4g8 .yevf $^4_2He$ is 28 MeV. What is its binding energy per nucleon?

  In the absence of the strong nuclear force, a large nucleus would be even more ui7jnjwn .jwj0 a6wsm5z( ;8ljnstable than a small nucleus. Which onejjwn 60w j (mn8.7ws;zi5aljj of the following is the best explanation?

  An element X is bombarded with alpha par/ivf. 4 mqe;isgn36zn ticles and a new element Y is formed with a neutron emitted. The following in/izgsq 6n.3e;m 4f vequation can be written for the nuclear reaction.

The atomic numbers of X and Y are A and B respectively. Which of the following is correct for A and B?

  Consider the following statementsdt -k uo7p+1ob about nuclear binding energy:
The nuclear binding energy is:
I. proportional to the mass defect from nucleus formation.
II. the energy released when a nucleus is formed from its nucleons.
III. the energy required to remove a proton from the nucleus.
Which of the statements are correct?

  A nuclide of a radioactive element Q can be represented as5i 4n.mjd(+yu wm*p0a 4vzui:;iyypa $^{234}_{90}Q$. The nuclide undergoes two negative beta decays and one alpha decay. Which of the following configurations correctly represents the daughter nuclide R?

The graph shows the variation of the measured activitfiastqnx- (;x.gvb2 qh7g2e-y of an isotope sample withehifgxv2--; s (7n btaxgqq2. time.

1.State what is meant by activity.
2.Explain why the activity graph doesn’t approach zero as time increases.
3.The activity graph is corrected so as to reach zero as time increases as shown below.

(1)Determine the half-life of the sample.
(2)The initial mass of this sample was 248 g. Determine the time that would elapse before 31 g of the sample remained.

  A 1.20 kg sample of a radioactive isotope decajbz1(-vm) j g1qayo c(ka9g8l mtw53cying via beta decay with a half-life of 30 minutes is observed in a closed container in a laboratory. The decay results in a daughter nucleus that is also a wlyj15to g accav(z(9g m bk3mq)j18-solid. What is the approximate total mass measured after 90 minutes?

  The activity of a 100% pure radioactive sample iqz f*r2zm7(9yb vbdvel,*7 y gs $10^6\,Bq$. The activity of the sample after 20% of nuclei have decayed is:

  During experiments observing beta decays, it was seen that the e cpxwl+9 siq 5,bkvb09nergy spectrum of the beta particles 95+qs vbklpw,bi90c xis continuous and momentum conservation was violated in beta decays. This provided evidence for the existence of:

  Which of the following radioactive decays can cause the production:d 2xguc ;h+qk of a daughter nucleus to be a different element than the p2 q: xukgdc+h;arent nucleus?
I. α decay
II. β decay
III. γ decay

  A pure radioactive sample of mass m has a decay constazlfve1l6:i* p nt of λ. Its activity is gievlf*6z : ipl1ven by A. Another pure sample of the same material has a mass 2m. Consider the following statements about the sample of mass 2m after an interval of two half lives.
I. The decay constant is $\frac{λ}{2}$​.
II. The activity is $\frac{A}{2}$​.
III. The mass of decayed nucleons in the sample is $\frac{m}{2}$​.
Which of the statements is/are correct?

  The binding energy pl 1wqc 8mj +ysl/zzefqx( 1.j3er nucleon of a $^A_ZX$ nucleus is E. What is the mass defect for the formation of X from its constituent nucleons?

1.The following reaction o 2 fsl6+ bps2rzqxpes;a4t8qk p i553takes place in a nuclear reactor:
$^{235}_{92}U$+$^1_0n$→$^{144}_{56}Ba$+$^{89}_{36}Kr$+$3^1_0n$
(1)Differentiate between fission and fusion reactions.
(2)Determine whether this reaction is a nuclear fission or nuclear fusion.
2.The following data is given for this reaction:
The binding energy per nucleon of $235^​U$ = 7.59 MeV
The binding energy per nucleon of $144​^Ba$ = 8.27 MeV
The binding energy per nucleon of $89^​Kr$ = 8.62 MeV
Calculate the energy released from this reaction.

  A nucleus $A^​$X has a mass defect of N unified atomic mass units, Nu. What is the correct expression for its binding energy per nucleon?

  1.Uranium-235 $(^{235}_{92}​U)$ has a nuclear mass of 235.044 u.
(1)State what is meant by mass defect.
(2)Calculate the mass defect of uranium-235. $δ$ =    $u$
2.(1)Calculate the binding energy per nucleon of uranium-235. $binding energy per nucleon$ =    $MeV$
(2)On the axes given, sketch the variation of the binding energy per nucleon with the nucleon number. Label the position of uranium-235. There is no need to add numbers to the axes.

3.Uranium-235 ( $^{235}_{92}​U$) decays into thorium-231 ( $^{231}_{90}Th$).
Determine which nuclide has a higher binding energy per nucleon. Use the graph to justify your answer.

1.Define decay constki.9v *o0y) 6r r.vsmsljmyt(ant.
2.Mushrooms contain a radioactive element called caesium-137, $^{137}_P{55}$​Cs . The element has a half-life of 30$yr$ and a sample of living mushrooms has a constant decay rate of 2000 2000Bq for every kg of mass. A sample of 50g is extracted from a dried mushroom and the activity is measured as 0.80Bq.
(1)Caesium-137 decays to barium-137, $^{137}_{56}Ba$, by beta emission. Complete the nuclear reaction equation of this decay, showing both particles emitted in the decay.
$^{137}_P{55}$​Cs→ ______ +$^{137}_{56}Ba$ + ______
(2)Show that the decay constant of caesium-137 is about 0.023 $yr^{−1}$.
(3)Given that the amount of caesium in the mushroom stops being replenished once the mushroom is no longer living, determine the age of the dried mushroom.
3.Some other radioactive substances have half-lives of thousands of years. Outline the method used for determining the half-life of these kinds of substances.

  A stationary nucleus of ug rm5t:wk r4r-ranium-238 undergoes alpha decay to form thorium-234. The initial speed of the alpha particle is v. What is correct about the m5wm:4trkrr-g agnitude of the thorium-234 velocity and its direction?

The plutonium isotopq1cuw1z3 0dfy*1 oex 5irtn7be $^{238}_{94}​Pu undergoes alpha decay.

1.Define isotope.
2.Rewrite this decay equation, filling in any missing information.
3.Plutonium undergoes a decay series. The graph below shows a part of this decay series.

(1)One type of decay cannot be represented on this diagram. Outline this type of decay and justify your answer.
(2)State the type of decay of $^{230}_{90}​Th$ that is represented on the diagram above. Justify your answer.
(3)Isotope X undergoes an alpha decay followed by a beta minus decay to produce isotope Y. Label the position of isotope Y on the diagram.
4.Compare the penetrating powers of alpha, beta and gamma radiation.