Multiple choice The chemical properties of U-235 will be similar to the: Pa-233 Pa-235 U-233 Pb-206 Reveal answer Fill a bubble to check yourself C Correct answer Explanation The isotopes have the same atomic number (number of protons), the same number of electrons, but a different atomic mass because the number of neutrons is different. U-233 is an isotope of U-235 so, their chemical properties are similar.