Final answer:
Carbon-14 has two more neutrons than carbon-12.
Step-by-step explanation:
Carbon-14 (14/6C) differs from carbon-12 (12/6C) in having two more neutrons than carbon-12. The atomic number of carbon is 6, which means that it has 6 protons. Both carbon-12 and carbon-14 have 6 protons, but carbon-14 has 8 neutrons while carbon-12 has 6 neutrons.