An electron in the ground state absorbs a single photon of light and then relaxes back to the ground state by emitting an infrared photon (1200 nm) followed by an orange photon (600 nm). What is the wavelength of the absorbed photon? A. 400 nm
B. 600 nm
C. 1800 nm

Pauling and lewis questioned the extreme definitions of bonds. they wondered if bonds might be described somewhere in between the two extremes (covalent and ionic). on the basis of experimental data,pauling confirmed that bonds could be ionic, covalent, and for those, in between, exhibit a degree of ionic character. he theorized that the major factor was how strongly the atoms in the bond attracted the electrons. pauling called this factor - the tendency of an atom to attract electrons in a bond.

Oil rich countries in the middle east cover about 4% of earths total land area but prossess about 48% of the worlds known oil reserves what is the main reason for high concentration of reserves in this part of the world

State one important difference between a physical change and a chemical change?