a. Number of protons in the nucleus, most to least: B=C, A. b. Number of neutrons in the nucleus, most to least: C, A=B . c. Number of electrons that normally surround the nucleus, most to least: B=C, A.
Work Step by Step
a. The number of protons is the atomic number. Uranium has an atomic number of 92, and thorium has an atomic number of 90. b. U-238 has 238 - 92 = 146 neutrons. Th-233 has 233 - 90 = 143 neutrons. U-235 has 235 - 92 = 143 neutrons. c. The number of electrons normally equals the number of protons (i.e., the atomic number).