Calculate the wavelength in nanometers of the light emitted by a hydrogen atom when it's electron falls from the n= 7 to the n= 4 principal energy level. Recall that the engergy levels of the H atom are given by En = -2.18 x 10 to the negative 18 J ( 1/n to the second power) . ( c= 3.00 x 10 to to the 8 th power m/s ; h=6.63 x 10 to the negative 34 j. s

Time remaining 58: 10 an atom that has 84 protons and 86 neutrons undergoes a reaction. at the end of the reaction, it has 82 protons and 84 neutrons. what happened to the atom? it accepted radiation in a chemical reaction it donated neutrons to another atom in a chemical reaction it emitted an alpha particle in a nuclear reaction. it accepted protons in a nuclear reaction. mark this and retum save and exit next submit