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wbruton
Oct 19, 2013, 05:06 PM
Hey, I would greatly appreciate if someone could help me with this lab:

I have mass of 100 ml of --
Propane .274
Butane .361
Methane .100

And the Molecular Weight
Propane 44.10 g/mol
Butane 58.12 g/mol
Methane 16.04 g/mol

Number of moles in the 100 ml samples... I got .0062... is that even right?

I'm not sure if I did the average for average number of moles right...

2. To verify Avogadro's Law, calculate the average number of moles for the three gases along with the percent deviation for each gas, according to the formula:

% deviation = |(moles of gas) - (average for all gases)| / (average for all gases) * 100%

I got .0186

I need to know percent deviation and if my results should confirm Avogadro's Law...



Also, the second half of the lab that is extremely complicated :
3. Volume occupied by one mole of gas at STP. One mole of any gas at STP conditions (standard temperature and pressure) occupies 22.4 liters. See how well the average number of moles for the gases agrees with this.

(a) Calculate the volume occupied by one mole of gas from the average number of moles in the 100 mL volume using the following proportionality equation:

Average moles / 100 mL = 1 mole / (volume of 1 mole)


(b) You should get something close to 22.4 L. This number must then be corrected for non-STP conditions in the lab as follows.

For ideal gases, PV/T is constant, and at STP, P=1 atm, V=22.4L, T=273.15K (0C).

Solve for the corrected volume at the lab temperature and pressure. Recalculate the expected moles in the corrected volume at lab temperature and pressure.

Report your experimental results using the corrected volume for 1 mole of gas, along with the percent deviation.


(c) Explain what might have caused your value to differ from the accepted value.




If anyone could answer just one of the questions, I would really appreciate it! Thanks in advance!