The nucleus of an atom contains six neutrons and esix protons. The nucleus of a second atom contains six neutrons and five protons. Are they atoms of different elements or isotopes of the same element?

To determine if the two atoms are different elements or isotopes of the same element, we need to compare their atomic numbers. The atomic number represents the number of protons in an atom.

In the first atom, the nucleus contains 6 protons, and in the second atom, the nucleus contains 5 protons.

Since the atomic number of an element determines its identity, it is clear that these two atoms have different atomic numbers. Therefore, they are atoms of different elements.

To determine whether the two atoms are different elements or isotopes of the same element, we need to understand the concepts of elements and isotopes.

An element is defined by the number of protons in its nucleus. Each element has a unique number of protons. For example, carbon is the element with six protons.

Isotopes, on the other hand, are variants of an element that have the same number of protons but different numbers of neutrons. Isotopes of an element have the same atomic number (number of protons) but different atomic masses (sum of protons and neutrons).

In the given scenario, we have two atoms with different compositions of protons and neutrons. The first atom has six protons and six neutrons, and the second atom has five protons and six neutrons. Since the number of protons is different in both atoms, they belong to different elements.

Therefore, these two atoms are atoms of different elements, not isotopes of the same element.

Since this is not my area of expertise, I searched Google under the key words "neutron proton elements isotopes" to get these possible sources:

http://home.earthlink.net/~kdthrge/sub3.htm
http://www.mcwdn.org/Physics/Atoms.html
http://web.jjay.cuny.edu/~acarpi/NSC/3-atoms.htm
http://en.wikipedia.org/wiki/Isotope

After reading the information in these sites, you should be able to answer your own question. In the future, you can find the information you desire more quickly, if you use appropriate key words to do your own search.

I hope this helps. Thanks for asking.