The relation between molecular (formula) mass and molar mass Page 4 4 • To obtain one mole of copper atoms (6.02 x 1023 atoms), weigh out 63.55 g copper. The molar mass (M) of a substance is the mass of one mole of entities (atoms, molecules, or formula units) of the substance.
Atomic number = protons
Protons = P Electrons = E P = E
Atomic mass = Neutrons + Protons
Atomic number = atomic mass = neutrons
P = E
AM - AN = N
Example:
Calcium = 20 Protons 20P = 20E
Atomic mass - atomic number = neutrons :)
That number has 6 significant numbers. It's precision would be 602.
Hope it helped.
Answer:
Explanation:
The nucleus of an atom contains neutrons and protons bonded tightly together. The same chemical element can have a different number of neutrons and still be the same element.