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Collecting Gas Over Water

APCHEM-LUEYGT

The forces that hold a gas together are dependent on the strength of the intermolecular forces of the substance and the interaction with the solvent. When collecting gas over water, the water vapor pressure, water temperature, and pressure of the room must be measured.

Based on gas law knowledge, an error in a lab calculation of the gas sample pressure would most likely result from which of the following?

A

Taking an incorrect temperature of the water due to leaving the thermometer in the water too long.

B

Recording an incorrect room pressure due to windows and doors being open in a laboratory causing fluctuations in room pressure.

C

Incorrectly recording the water vapor pressure based on the water temperature from a reliable source.

D

Incorrectly lining up the water levels inside and outside the gas collection bottle.