Using the periodic table, elaborate the difference between the number of electrons in an oxygen-16 atom and an oxygen-18 atom.

Question

Responses
A These configurations differ in their number of electrons - so they contain 8 and 9 electrons, respectively.These configurations differ in their number of electrons - so they contain 8 and 9 electrons, respectively.
B Allotropes vary in their number of electrons - so oxygen-16 and oxygen-18 contain 8 and 10 electrons, respectively.Allotropes vary in their number of electrons - so oxygen-16 and oxygen-18 contain 8 and 10 electrons, respectively.
C Oxygen atoms fluctuate in their number of electrons - so oxygen-16 and oxygen-18 contain 7 and 9 electrons, respectively.Oxygen atoms fluctuate in their number of electrons - so oxygen-16 and oxygen-18 contain 7 and 9 electrons, respectively.
D The number of electrons are the same for all isotopes of an element - so both oxygen-16 and oxygen-18 contain 8 electrons

Answer 1

The correct choice is D: "The number of electrons are the same for all isotopes of an element - so both oxygen-16 and oxygen-18 contain 8 electrons."

Here's the reasoning:

Oxygen, regardless of its isotope (Oxygen-16 or Oxygen-18), has 8 electrons. The isotopes differ in the number of neutrons in the nucleus. Oxygen-16 has 8 neutrons (8 protons + 8 neutrons = 16), while Oxygen-18 has 10 neutrons (8 protons + 10 neutrons = 18). However, the number of electrons in a neutral oxygen atom is always equal to the number of protons, which is 8 for oxygen. Therefore, both isotopes have the same number of electrons, which is 8.