Question

1. the scientist noticed that at the end of the combustion analysis, a colorless and odorless gas was coming out of the device. however, she does not know if that gas is just oxygen gas or a mixture of oxygen and additional gases (that may contain other elements). what could she do to determine if the gas coming out of the device is just oxygen gas or a mixture of gases? a. compare the odor of the gas with pure oxygen gas. b. rerun the gas through the device to isolate pure oxygen gas. c. compare the visual appearance of the gas with pure oxygen gas. d. test the flammability of the gas in comparison with pure oxygen gas.

Explanation:

Pure oxygen is odorless and colorless, so comparing odor or visual appearance (options A and C) cannot distinguish pure oxygen from a mixture with other odorless/colorless gases. Testing flammability (option D) is not effective because oxygen supports combustion but is not flammable itself. Isolating pure oxygen by rerunning the gas through the device (option B) would separate any additional gases, allowing confirmation if the output is pure oxygen or a mixture.

Answer:

B. Rerun the gas through the device to isolate pure oxygen gas.