Given that oxygen-16 and oxygen-18 both have an atomic number of 8, how many electrons, protons, and neutrons do these oxygen atoms contain?

Atomic number Z = 8

as atomic number is equal to number of protons So, there are 8 protons in the oxygen 16 and oxygen 18

And number of protons is equal to number of electrons so there are 8 electrons in both oxygen 16 and oxygen-18.

Number of neutrons = Mass number - Atomic number

so, number of neutrons in oxygen-18 = 18 - 8 = 10

and number of neutrons in oxygen-16 = 16 - 8 = 8