Answer:
B. All carbon atoms have six protons and six electrons.
D. Atoms of some naturally occurring carbon isotopes may have six neutrons
Step-by-step explanation:
Isotopes are atoms of the same elements having same atomic number but different atomic masses.
Atomic number is the number of protons (or electron number in neutral atoms) present in the atomic nucleus of the atom.
Atomic mass number is the sum of protons and neutrons present in the nucleus of the atom.
Considering the options above from the above definitions:
A. All carbon atoms have six neutrons is false because carbon-12, carbon-13 and carbon-14 has 6, 7 and 8 neutrons respectively.
B. All carbon atoms have six protons and six electrons is true because the atomic number of carbon is 12.
C. Atoms of all carbon isotopes have either more than 6 electrons or fewer than 6 electrons is false because atoms of all carbon isotopes have six electrons.
D. Atoms of some naturally occurring carbon isotopes may have six neutrons is true because atoms of carbon-12 have six neutrons.
E. Atoms of some naturally occurring carbon isotopes may have twelve neutrons is false because none of carbon-12, carbon-13 or carbon-14 have twelve neutrons.