This manuscript presented the retention coefficients of trace gases in the freezing rain size droplets. This study used acoustic levitator to freeze droplets initiated by silver iodide and then measured the remained substances in the frozen droplets. The pH and temperature dependences are also investigated. New parameterization of the retention indicator are proposed. The topic of this study fits the scope of this journal. This manuscript is well written. There are several issues need to be addressed before publication.

Major comments:

1. L35-58, do we expect significant difference in retention of volatile gases regarding the physical mechanism between cloud and rain droplets? A better rationalization focusing on rain droplet size is needed.
2. L95, this study only investigated at concentration of 20 mg/L. What are the typical concentrations of investigated substances in the real rain drops? Are the retention coefficients also depending on the initial concentrations?
3. Section 3.2, for higher pH, NaOH is used to control the pH of the solution. There is no H⁺ for the investigated acids to be partitioned into gas phase, so of cause the retention coefficient would be close to 1 even without freezing. Please comment on this.

Other comments:

1. Title, Retention of what? It is suggested to include the subjects in the title. It would be more specific.
2. L8, which physical properties?
3. L50, which studies mentioned? Please be specific.
4. Section 2.1, what are the temperature uncertainties?
5. L352, temperature at f_ice of 50% is the median freezing temperature, not mean/average.
6. Missing page information for some references.