No, an atom with 3 protons and 3 neutrons is not a lithium atom. It is actually a different element called helium-6 (He-6). Lithium, with the atomic number 3, has 3 protons in its nucleus, but its most common isotope has 4 neutrons, giving it a total of 7 nucleons. So, a lithium atom typically consists of 3 protons and 4 neutrons.
On the other hand, an atom with 3 protons and 4 neutrons is not a lithium atom either. It is actually an isotope of the element beryllium, specifically beryllium-7 (Be-7). Beryllium normally has 4 protons, but the presence of an additional neutron makes it a different isotope.
To summarize:
- Atom with 3 protons and 3 neutrons: helium-6 (He-6)
- Atom with 3 protons and 4 neutrons: beryllium-7 (Be-7)
- Atom with 3 protons and 4 neutrons is not a lithium atom