Two stable isotopes of lithium \(^{6}_{3}\mathrm{Li}\) and \(^{7}_{3}\mathrm{Li}\) have respective abundances of \(7.5\%\) and \(92.5\%\). These isotopes have masses \(6.01512~\text{u}\) and \(7.01600~\text{u}\), respectively. The atomic mass of lithium is:
1. \(6.940934~\text{u}\)
2. \(6.897643~\text{u}\)
3. \(7.863052~\text{u}\)
4. \(7.167077~\text{u}\)
The three stable isotopes of neon: have respective abundances of 90.51%, 0.27%, and 9.22%. The atomic masses of the three isotopes are 19.99 u, 20.99 u, and 21.99 u, respectively. The average atomic mass of neon is:
1. 20.1709 u
2. 21.7037 u
3. 20.1771 u
4. 21.0097 u
What is the binding energy (in MeV) of a nitrogen nucleus ?
1. 102.7 MeV.
2. 100.7 MeV.
3. 104.7 MeV.
4. 108.7 MeV.
A given coin has a mass of 3.0 g. How much nuclear energy would be required to separate all the neutrons and protons from each other? For simplicity assume that the coin is entirely made of atoms (of mass 62.92960 u).
1. \(2.5296\times10^{12}\) MeV
2. \(1.581\times10^{25}\) MeV
3. \(3.1223\times10^{20}\) MeV
4. \(931.02\times10^{19}\) MeV
The radionuclide \(^{11}_{6}C\) decays according to \(^{11}_{6}C \rightarrow ~^{11}_{5}B+e^{+}+\nu\): \(\left(T_{\frac{1}{2}}=20.3~\text{min}\right)\)
The maximum energy of the emitted position is \(0.960~\text{MeV}\).
Given the mass values:
\(m\left(_{6}^{11}C\right) = 11.011434~\text{u}~\text{and}~ m\left(_{6}^{11}B\right) = 11.009305~\text{u},\)
The value of \(Q\) is:
1. \(0.313~\text{MeV}\)
2. \(0.962~\text{MeV}\)
3. \(0.414~\text{MeV}\)
4. \(0.132~\text{MeV}\)
The nucleus decays by β– emission. What is the maximum kinetic energy of the electrons emitted? Given that:
m () = 22.994466 u
m () = 22.989770 u.
1. 4.201 MeV
2. 3.791 MeV
3. 4.374 MeV
4. 3.851 MeV
The fission properties of are very similar to those of . The average energy released per fission is 180 MeV. How much energy, in MeV, is released if all the atoms in 1 kg of pure undergo fission?
1. \(2.5\times 10^{25}\) MeV
2. \(4.5\times 10^{25}\) MeV
3. \(2.5\times 10^{26}\) MeV
4. \(4.5\times 10^{26}\) MeV
What is the height of the potential barrier for a head-on collision of two deuterons? (Assume that they can be taken as hard spheres of radius 2.0 fm.)
1. 300 keV
2. 360 keV
3. 376 keV
4. 356 keV
The neutron separation energy is defined as the energy required to remove a neutron from the nucleus. The neutron separation energies of the nuclei \(_{20}^{41}\mathrm{Ca}\) is:
Given that:
\(\begin{aligned} & \mathrm{m}\left({ }_{20}^{40} \mathrm{C a}\right)=39.962591~ \text{u}\\ & \mathrm{m}\left({ }_{20}^{41} \mathrm{C a}\right)=40.962278 ~\text{u} \end{aligned}\)
1. \(7.657~\text{MeV}\)
2. \(8.363~\text{MeV}\)
3. \(9.037~\text{MeV}\)
4. \(9.861~\text{MeV}\)
Consider the fission of \(_{92}^{238}\mathrm{U}\) by fast neutrons. In one fission event, no neutrons are emitted and the final end products, after the beta decay of the primary fragments, are \({}_{58}^{140}\mathrm{Ce}\) and \({}_{44}^{99}\mathrm{Ru}\). What is \(Q\) for this fission process? The relevant atomic and particle masses are:
\(\mathrm m\left(_{92}^{238}\mathrm{U}\right)= 238.05079~\text{u}\)
\(\mathrm m\left(_{58}^{140}\mathrm{Ce}\right)= 139.90543~\text{u}\)
\(\mathrm m\left(_{44}^{99}\mathrm{Ru}\right)= 98.90594~\text{u}\)
1. \(303.037~\text{MeV}\)
2. \(205.981~\text{MeV}\)
3. \(312.210~\text{MeV}\)
4. \(231.007~\text{MeV}\)