A 30-L Sample of Helium Was Placed in Container Fitted with with a Porous

question 1

Multiple Choice

A 3.0-L sample of helium was placed in container fitted with a porous membrane. Half of the helium effused through the membrane in 24 hours. A 3.0-L sample of oxygen was placed in an identical container. How many hours will it take for half of the oxygen to effuse through the membrane?

• A) 8.5 h
• B) 12 h
• C) 48 h
• D) 60. h
• E) 68 h

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Definitions:

Auricle

The external portion of the ear, which captures sound waves and directs them into the ear canal.

External Auditory Canal

Short canal that opens to the exterior environment and terminates at the eardrum; part of the external ear.

Eardrum

Cellular membrane that separates the external from the middle ear; vibrates in response to sound waves; also called tympanic membrane.

Inner Ear

The innermost part of the ear, containing the cochlea, vestibule, and semicircular canals, responsible for sound detection and balance.