According to the wave-mechanical model of the atom, electrons in an atom
(1) travel in defined circles
(2) are most likely found in an excited state
(3) have a positive charge
(4) are located in orbitals outside the nucleus

4al + 3o2 → 2al2o3 what does the "3" in front of o2 stand for? a) it indicates that there are 5 oxygen atoms after you add the coefficient and the subscript. b) it indicates that that there are are total of 6 oxygen atoms all bonded together as a single molecule. c) it indicates that there are 3 oxygen molecules chemically bonded to each other in the reaction. d) it indicates that there are 3 separate oxygen molecules in the reaction.