Photon
Photon
A quantum of energy in the form of light with a value of Planck’s constant multiplied by the
frequency of the light.
Physical property
Physical property
A property of a substance related to its physical, not chemical, characteristics; e.g., density,
smell, color.
Pi (π) bond
Pi (π) bond
A covalent bond formed by parallel overlap of two unhybridized atomic p orbitals.pOH
pOH
A measure of the hydroxide (OH–) ion content of an aqueous solution, defined to be equal to the
negative log of the OH– concentration.
Polar covalent bond
Polar covalent bond
A covalent bond between atoms with different electronegativities in which electron density is
unevenly distributed, giving the bond positive and negative ends.
Polar molecule
Polar molecule
A molecule possessing one or more polar covalent bond(s) and a geometry that allows the bond