Consider the following reaction 2Mg(s) + 02 (9) 2Mgo (s)
If 21.2 kcals of energy is released by this reaction, how many kJ
of energy does the reaction release? (1 cal = 4.184 J) (Round off
decimal to nearest tenths)

The nuclear potential that binds protons and neutrons in the nucleus of an atom is often approximated by a square well. imagine a proton conned in an innite square well of length 105 nm, a typical nuclear diameter. calculate the wavelength and energy associated with the photon that is emitted when the proton undergoes a transition from the rst excited state (n 2) to the ground state (n 1). in what region of the electromagnetic spectrum does this wavelength belong?