To evaluate the statements regarding the residence times of chemicals and the comparison between the atmosphere and oceans, let's analyze each statement based on the given knowledge about geology and hydrogeology.

Statement 1 Analysis: "Residence times of chemicals in the atmosphere are usually longer than those in the oceans."

This statement is generally false. The atmosphere is a dynamic system with higher rates of exchange and turnover compared to the oceans. For many chemicals, especially volatile substances, the residence time in the atmosphere is shorter than in the oceans because atmospheric processes like wind, precipitation, and chemical reactions act to remove or transform these substances more quickly. The ocean acts as a relatively larger and more stable reservoir where chemicals can remain for longer durations due to slower mixing and fewer removal processes.

Statement 2 Analysis: "In terms of total mass, the atmosphere is a smaller reservoir than the oceans, and fluxes into and out of the atmosphere can be larger."

This statement is true. The mass of the Earth's atmosphere is much smaller than that of the oceans. Given its smaller mass, the atmosphere experiences larger fluxes relative to its size, as it exchanges materials rapidly with both the oceans and the land through processes like evaporation, precipitation, and gas exchange. This dynamic exchange further supports the earlier analysis that residence times in the atmosphere are usually shorter.

Conclusion:

Correct Answer: Statement 1 is false but statement 2 is true.

Therefore, option "Statement 1 is false but statement 2 is true." is correct. Statement 2 accurately describes the relationship between the atmosphere and oceans and provides context for understanding residency and fluxes between these natural reservoirs.