20.

Question 20 4 pts The binding energy per nucleon of a nucleus O has a minimum near iron in the periodic table and then increases for heavier elements. O increases steadily as the elements become heavier. O decreases steadily as the elements become heavier. O has a maximum near iron in the periodic table and then decreases for heavier elements. O is nearly constant throughout the periodic table.Question 21 4 pts An alpha particle is also known as a O gamma ray photon proton positron electron O helium nucleusQuestion 22 4 pts The atomic number and mass number for a certain isotope of calcium are 20 and 39, respectively. How many nucleons are in one atom? 0 59 O 20 0 39 O 19 01Question 23 4 p A radioactive isotope of atomic number Z emits a beta-minus particle, and then the daughter nucleus emits a gamma ray. What is the atomic number of the resulting nucleus after both processes? oz+1 OZ-2 OZ oz-1 OZ - 4Question 24 4 pts The element radium contains 88 protons. The masses of the neutron, hydrogen atom, and radium-226 isotope are m. - 1.008665 u , MH = 1.007825 u , and mRa = 226.025403 u. What is the binding energy of the radium-226 isotope? 0 1700 MeV O 2300 MeV O 2100 MeV 1900 MeV O 2500 MeVQuestion 25 4 pts If the half-life of an isotope is 45 years, how much of that isotope will be left after 100 years? more than 1/4 but less than 1/2 more than 1/2 O less than 1/8 O more than 1/8 but less than 1/4 90%