Dear Authors:
After carefully reviewing the response to the referees’ comments and the revised documents I have determined that further revisions are necessary prior to acceptance. Please consider the comments below. All line numbers refer to the track changes version of the manuscript. Thank you.
Major:
Sect 3.3: The log(Kp) vs log(VPt) results should be discussed in more detail. For instance, according to Pankow (1994) the slope of this plot should be about -1. For the alkanals, the slope is sometimes positive. Please discuss. Since samples were collected for 24 h, how was the temperature determined? How does the diurnal evolution of temperature affect the results?
Table 2: The % of n-alkanals in the particle phase is surprisingly high for the low C number species. Please comment on this.
Minor:
Abstract: Please make it clear that both gas- and condensed-phase measurements were made as part of this work.
Sect 2.3: Please also include limit of detections for the compounds as this becomes a point later on in the manuscript. Also, please add information on breakthrough that was included in the response to Referee 2. What exactly is meant by “minimal breakthrough for alkanes >= C11”? Was loss of gas-phase compounds to the filters investigated?
Line 208: The time series is Figure 3 not 2. Please ensure that all figures are referenced in order and that the correct figure is referenced in the text throughout the manuscript.
Line 214-216: These references did not specifically identify the position of the carbonyl group. Please revise.
Line 228-229: Wouldn’t this be independent of NO concentration if the issue is reaction with O2 vs isomerization?
Line 252-253: I am not convinced that the difference in concentration is a “clear indication of road traffic.” I would expect that the urban measurements would also be influenced by traffic. More details regarding the previous work (site locations, temperature, time of year, etc.) needs to be provided if this sentence remains.
Line 261: Please define Cmax the first time it is used.
Line 286: CPI is used before it is defined. Please correct this.
Line 347-348: Please be more explicit about what is meant by “significant particulate fraction” and “low MW.”
Line 355-357: For alkanes of this size, isomerization in the gas-phase dominates over fragmentation. As such I would think that decomposition products would likely be multifunctional. I would also expect that aldehydes would be preferentially formed as a result of fragmentation. Please clarify how this could occur.
Line 365-366: Please clarify that homogeneous means gas-phase.
Table S4 I see data for only RU and WM sites, however, the caption says that it includes data for El and MR site. Please fix.
Lines 582-588: This seems better suited for Sect. 3.3 then for the conclusions.

Congratulations.