. "mole concentration of isoprene in air" . " Mole concentration means number of moles per unit volume, also called \"molarity\", and is used in the construction mole_concentration_of_X_in_Y, where X is a material constituent of Y. A chemical species denoted by X may be described by a single term such as 'nitrogen' or a phrase such as 'nox_expressed_as_nitrogen'. The chemical formula for isoprene is CH2=C(CH3)CH=CH2. The IUPAC name for isoprene is 2-methyl-buta-1,3-diene. Isoprene is a member of the group of hydrocarbons known as terpenes. There are standard names for the terpene group as well as for some of the individual species." . "Climate and Forecast (CF)" . . .