Chemistry 2 moles of H20 heated at 10A for 1hr. What is the volume?

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The discussion centers on calculating the volume of gas produced from the electrolysis of 2 moles of water at 10A over one hour. Using Faraday's Law, participants calculated the mass of hydrogen and oxygen gas generated, resulting in a total of 3.358g of gas. However, there was confusion regarding the final volume, as the initial volume of water was 36mL, and the calculations did not account for the pressure and temperature conditions necessary to determine the total system volume accurately. It was noted that the question's wording may have contributed to misunderstandings about whether to include the gas volume in the final calculation. Overall, the conversation highlighted the complexities of electrolysis calculations and the importance of clear problem statements.
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Homework Statement


2 moles of water undergoes electrolysis at 10A. What is the total volume of the system after 1hr?

Homework Equations


4 H+(aq) + 4e−→ 2H2(g)

2 H2O(l) → O2(g) + 4 H+(aq) + 4e−

Faraday's Law of Electrolysis
Q = n(e-) x F

F = 96500C

The Attempt at a Solution



Initial volume = 36mL

Gas produced
(10*3600s*4g)/(F*4)=0.373g H2

(10*3600s*32g)/(F*4)=2.984g O2

0.373g+2.984g=3.358g

Final volume
36mL+3.35mL =39.358mL
 
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3.358 rounds up to 3.36
3.358g of gas does not make 3.358mL of gas.
If you start with 36g of H2O and you remove some of the H and some of the O you do not end up with 36g.
 
I apologize. I'm very new to chemistry. I thought I was solving for total volume including the expanding gas.

Final volume
36mL-3.35mL =32.65
 
You can't calculate total volume of "the system" not knowing the pressure and the temperature. Perhaps it is just a matter of lousy wording of the question, or you are expected to assume STP.

What you have found is the volume of water left. This is not total volume occupied.
 
Borek said:
You can't calculate total volume of "the system" not knowing the pressure and the temperature. Perhaps it is just a matter of lousy wording of the question, or you are expected to assume STP.

What you have found is the volume of water left. This is not total volume occupied.

Yes, it was very poor wording. Still new to writing these equations. Thank you for your help.
 
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