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Chemistry Forums for Students => High School Chemistry Forum => Topic started by: kelaklub on May 08, 2006, 02:11:41 PM

Title: Diffusion rate
Post by: kelaklub on May 08, 2006, 02:11:41 PM

The following is a practise test question...

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Question

The diffusion rate of methane gas compared to that of helium is...

A) twice as fast
B) 4 times as slow
C) 4 time as fast
D) half as fast
E) 12 times as fast

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The answer is supposed to be choice D. But I picked choice B, basing the diffusion rate on the atomic weights.

So does diffusion rate only depend on the number of elements present, 2 in methane (C and H), and He. Thanks.

Title: Re: Diffusion rate
Post by: Borek on May 08, 2006, 02:27:16 PM

Graham's Law of Effusion

Title: Re: Diffusion rate
Post by: kelaklub on May 08, 2006, 02:29:28 PM

Aaah, the square root. Thank you very much.