Energy guide Cheat Sheet by ChemIsForSheeit

h= 6.63x10^-34J*s
c=3x10⁸ m/s

To identify a metal by its color

When the electron comes back to its ground­state

C=VA (A is lambda)
E=hV

Heat or electr­icity is applied to an atom, and the electron absorbs the energy and then gets excited; leaves its ground state, and comes back to its nucleus due to it being attracted, and then releases energy; Photon

1m=1x10⁹nm
1kHz=1x10³Hz
1mHz=1x10⁶Hz

(6.02x10²³)(6.63x10^-34)(V)

Multiply this exactly how this is once you get your V and you will get your mole of a photon for the problem.