Isotopes Original Scenario-Based Download PDF

Questions

1. 1.

   An automated survey drone exploring a subterranean cavern on an icy comet collects two pure reservoirs of a noble gas designated Element-Z. High-precision spectroscopy reveals that every neutral atom in both reservoirs contains exactly 10 protons and 10 electrons, yet the atoms in Reservoir 1 have a mass number of 20 while those in Reservoir 2 have a mass number of 22. Which statement correctly identifies the relationship between these two forms of Element-Z and explains the difference in their atomic structure?

   • A) They are isotopes of the same element because they possess identical proton numbers, but Reservoir 1 atoms have 10 neutrons whereas Reservoir 2 atoms have 12 neutrons.
   • B) They are distinct chemical elements because any difference in overall nuclear mass assigns atoms to entirely different elemental categories.
   • C) They are allotropes of Element-Z because their mass difference results from Reservoir 2 atoms holding two additional valence electrons.
   • D) They are isotopes of the same element because Reservoir 2 atoms contain two extra protons in the nucleus that are neutralized by two extra nuclear electrons.