Question

What are the assumptions we make when using the gas collection apparatus in this lab? (Select all that apply.)



We make no assumptions in this lab.


The pressure and temperature of the room remain constant.


The reaction begins after the test tube is capped, so CO2 is not lost to the atmosphere.


Percent recovery accounts for all the CO2 lost during water displacement after capping the test tube.

Answer 1

Selected:
- The pressure and temperature of the room remain constant.
- The reaction begins after the test tube is capped, so CO2 is not lost to the atmosphere.

Reasoning:
- We do make assumptions in this lab (so “no assumptions” is incorrect).
- Room temperature and pressure are usually treated as constant during the measurement for use with gas laws and pressure corrections.
- It’s typically assumed that the reaction (and significant CO2 evolution) occurs after capping so gas isn’t lost to the air.
- “Percent recovery accounts for all the CO2 lost…” is too strong/incorrect — percent recovery is an experimental correction/estimate for collection efficiency, not a guarantee it accounts for every possible loss.