Chemical Forums

Chemistry Forums for Students => High School Chemistry Forum => Topic started by: Blue on June 27, 2013, 05:29:50 AM

Title: Another problem
Post by: Blue 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?
Title: Re: Another problem
Post by: Borek on June 27, 2013, 05:34:42 AM
Start with the reaction equation.

Convert everything to moles.
Title: Re: Another problem
Post by: Blue on June 27, 2013, 05:59:01 AM
Quote from: Borek on June 27, 2013, 05:34:42 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
Title: Re: Another problem
Post by: Archer 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
Title: Re: Another problem
Post by: Blue on June 27, 2013, 06:57:39 AM
Quote from: Archer 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

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
Title: Re: Another problem
Post by: Borek on June 27, 2013, 07:23:19 AM
Actually exact answer depends on what it is meant by the "normal conditions".

http://www.youtube.com/v/H-TSkQl7zD4