Final answer:
No, Atom #1 with 19 protons and Atom #2 with 20 protons are not isotopes because isotopes must have the same number of protons but can have different numbers of neutrons.
Step-by-step explanation:
If Atom #1 has 19 protons and 22 neutrons, and Atom #2 has 20 protons and 22 neutrons, these are not isotopes of the same element. Isotopes are atoms of the same element that have the same number of protons but different numbers of neutrons. Since atoms #1 and #2 have different numbers of protons, they are different elements altogether and cannot be isotopes of each other.
Isotopes must have the same atomic number, which represents the number of protons in the nucleus; however, they have different mass numbers due to the variation in their neutron counts. For instance, carbon always has 6 protons, but isotopes of carbon can have 6, 7, or 8 neutrons, resulting in Carbon-12, Carbon-13, and Carbon-14 isotopes respectively.