# AP Chemistry

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I think this is a units issue, i keep getting the wrong answer.

the formula should be rate1/rate2= (molar mas 2/ molar mass1)^1/2

but every time i do it, i get it wrong, and when i do rate1/rate2= (molar mas 1/ molar mass2)^1/2, i get the right answer.

It takes 140 SECONDS for a sample of neon to effuse through a porus plug, how long does it take for the same volume of butane, C4H10 to effuse under the same conditions?

do i have to change seconds to anything? What unit does the law say rate is in?

• AP Chemistry -

If you get it "right" the second way, the machine determining right is in error.

rateH2/rateNe=sqrt (20/2) Appx, you do it more exact.
So rateH2= sqrt 10 *rate He appx....
so, the time for H2 will be about 1/sqrt10 times rate Ne, or about 44 sec to effuse.

It may be that you are using 140 as the rate, when in fact the rate is the INVERSE of the time to effuse.

• AP Chemistry -

How do u know if it is the inverse or not.
and you are not supposed to do 20/2
we are comparing the rate of neon to C4H10 correct?

• AP Chemistry -

Titanium metal can be produced from the reduction of titanium(4) chloride with magnesium metal to form solid titanium and magnesium chloride:write the balance equation for the reaction.