The atom that serves as the relative standard for determining mass and the number of particles in a mole is: A) Carbon-12 (C-12). B) Hydrogen (H). C) Oxygen (O). D) Nitrogen (N).
Carbon-12 is the most abundant isotope of carbon and has 6 protons, 6 neutrons, and 6 electrons. It is used as the standard for atomic mass and is assigned an atomic mass of exactly 12.
