A nuclear bomb explosion results in a mass decrease of

Question

1. The mass number for a particular atom with 45 neutrons is 80. How many protons does the atom have?

40
80
35
45

2. A nuclear bomb explosion results in a mass decrease of about between the initial and the final components. How much energy is released? Let the speed of light c = 3.00 x10⁸ m/s.

6.30 Af- 105 J
1.89 Af- 1017 J
2.25 Af- 1012 J
1.89 Af- 1014 J

3. A radioactive nuclide of atomic number Z emits an alpha particle, and then the daughter nucleus emits a beta particle. What is the atomic number of the resulting nuclide after both processes?
Z-2
Z+1
Z-3
Z-1

4. In a nuclear reaction, the total rest mass of the products is 0.003892 u greater than the total rest mass of the reactants. Is the reaction exoergic or endoergic, and what is the reaction energy Q? Let 931.5 MeV = 1 u.

endoergic; Q = -3.625 MeV
endoergic; Q = -7.823 MeV
exoergic; Q = 3.625 MeV
exoergic; Q = 7.823 MeV