Phosphorus trichloride is used in the production of chemicals that keep plants from growing in a specific area. This compound is made of phosphorus and chlorine atoms.
What two symbols would make up the chemical formula of this covalent compound?
O P and C
O P and CI
O Pr and Ce
O Prand Cr

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?