The Mauna Loa Observatory Photochemistry Experiment-II (MLOPEX-II), is an experimental program to study the chemical processing of nitrogenous, sulfurous, and carbonaceous compounds in the remote troposphere through a detailed examination of the chemistry of ozone and other oxidizing species. Two basic MLOPEX-II objectives have been formulated and are: to evaluate the concentration and variability of short-lived trace species on diurnal, synoptic and seasonal time scales and to assess photochemical models of the remote troposphere over an annual cycle. MLOPEX-II is a coordinated multi-institutional experiment involving universities, NCAR, and NOAA. The field portion of the experiment will be conducted through four six-week intensive measurement periods, one in each season, and will be located at the Mauna Loa Observatory, HI. The P.I. plans to make the following gas phase measurements as part of the MLOPEX-II program, batch measurements of hydrogen peroxide and specific organic hydroperoxides and formaldehyde. The first year will be spent making measurements, performing data reduction, and analyzing collected data. The second year will focus upon data analysis and interpretation.