Choose the correct definition of a mole.
the same number of particles in exactly 1 grams of hydrogen molecules
the same number of particles in exactly 14 grams of carbon-14
the same number of particles in exactly 12 grams of carbon-12
the same number of particles as in exactly 1 gram of hydrogen atoms
A mole is defined as the same number of particles in exactly 12 grams of carbon-12.