Gas exchange occurs when a. oxygen in the alveoli diffuses into the blood in the capillaries b. oxygen binds with hemoglobin in the red blood cells
c. the red blood cells give up oxygen to the cells of the body tissues
d. All of the above

Hydrogen has only one electron in its only (and outer) electron shell. if a hydrogen atom were to absorb a small amount of energy, where would bohr say the electron would go? a. fly off the atom b. nowhere, it would just speed up. c. spiral inwards towards the nucleus d. move up to another shell that would form