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Topic: Another problem  (Read 2540 times)

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Offline Blue

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Another problem
« on: June 27, 2013, 05:29:50 AM »
What is the volume of H2 (normal conditions) which gets released when we add 4.6g of elementary Na into 100g of pure ethanol?
« Last Edit: June 27, 2013, 06:31:39 AM by Blue »

Offline Borek

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Re: Another problem
« Reply #1 on: June 27, 2013, 05:34:42 AM »
Start with the reaction equation.

Convert everything to moles.
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Offline Blue

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Re: Another problem
« Reply #2 on: June 27, 2013, 05:59:01 AM »
Start with the reaction equation.

Convert everything to moles.

I did that, but I don't know what to do with Na? I'm a bit confused

Offline Archer

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Re: Another problem
« Reply #3 on: June 27, 2013, 06:27:32 AM »
With Sodium you only have to worry about the atomic mass of sodium which is 23.

You will need to work out which reactant (Na or EtOH) is in excess
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Offline Blue

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Re: Another problem
« Reply #4 on: June 27, 2013, 06:57:39 AM »
With Sodium you only have to worry about the atomic mass of sodium which is 23.

You will need to work out which reactant (Na or EtOH) is in excess

I found that C2H5OH is in excess, so Na is the limiting reagent. Therefore, n(H2) =0.1mol and V= n*Vm=0.1*22.4=2.24dm3, Thank you a lot

Offline Borek

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Re: Another problem
« Reply #5 on: June 27, 2013, 07:23:19 AM »
Actually exact answer depends on what it is meant by the "normal conditions".

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