Question

13C and 14C are isotopes of 12C, which has 6 electrons, 6 protons, and 6 neutrons. What is the arrangement of subatomic particles in 14C?

Answer 1

Isotopes of an element differs by the number of neutrons in the nucleus. "12" from 12C indicates the relative atomic mass of 12C. Both the proton and neutron amount to 1 relative atomic mass. Electrons have 0 relative mass. When compared to 12C, 13C is heavier. Think of what might make it heavier than 12C. Remember, if you change the number of protons, the atom will not be a carbon atom anymore. Hope that helps you with the question.