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Topic: Can someone help with this question?  (Read 3113 times)

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darkwizard267787

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Can someone help with this question?
« on: September 22, 2022, 12:01:53 PM »
A container contains a solution of HCl(aq)0.5M, someone added 12gr of Fe(s). The chemical reaction formed FeCl3(aq) and H2(g).
1. What is the volume of acid that reacted?
2. What is the concentration of the cations and the concentration of the anions in the solution (use the volume from the first question)?

Corribus

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Re: Can someone help with this question?
« Reply #1 on: September 22, 2022, 12:41:18 PM »
The forum rules require you to show your work to receive help.
What men are poets who can speak of Jupiter if he were like a man, but if he is an immense spinning sphere of methane and ammonia must be silent?  - Richard P. Feynman

Babcock_Hall

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Re: Can someone help with this question?
« Reply #2 on: September 22, 2022, 05:37:38 PM »
In general it is a good idea to write a balanced equation.

darkwizard267787

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Re: Can someone help with this question?
« Reply #3 on: September 23, 2022, 04:52:29 AM »
Hi, thank you for your response

This is what I have done
6HCl(aq)+2Fe(s) 3H2(g)+2FeCl3(aq)
0.5M=0.21mol/X
x= 0.42L
FeCl3(aq) H2OFe3++3Cl-

I just don't understand how to solve the second question
« Last Edit: September 23, 2022, 08:48:12 AM by billnotgatez »

Borek

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Re: Can someone help with this question?
« Reply #4 on: September 23, 2022, 07:17:46 AM »
How many moles of Fe3+? In what volume? What is the concentration of Fe3+ then?

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Enthalpy

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Re: Can someone help with this question?
« Reply #5 on: September 26, 2022, 05:40:29 AM »
Can the question be answered? I feel it lacks something like "both reactants are completely consumed".

Aldebaran

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Re: Can someone help with this question?
« Reply #6 on: September 26, 2022, 11:45:16 AM »
Yes it can be answered but I donâ€™t think the question is written very well.

Babcock_Hall

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Re: Can someone help with this question?
« Reply #7 on: September 27, 2022, 10:13:47 AM »
Can the question be answered? I feel it lacks something like "both reactants are completely consumed".
I think that when the question does not specify, it is fine to assume a complete reaction.

billnotgatez

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Re: Can someone help with this question?
« Reply #8 on: September 27, 2022, 10:24:43 PM »
@Babcock_Hall Do you think that making that assumption is a fair requirement for a High School student?

Can the question be answered? I feel it lacks something like "both reactants are completely consumed".
I think that when the question does not specify, it is fine to assume a complete reaction.

Borek

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Re: Can someone help with this question?
« Reply #9 on: September 28, 2022, 02:44:14 AM »
@Babcock_Hall Do you think that making that assumption is a fair requirement for a High School student?

It is a common assumption, it would be quite surprising to see a problem that doesn't use it.

Question is a bit strange, as it is not "volume of the acid that reacts", but "amount of acid that reacts", other than that it is just a kind of limiting reagent problem. Typical HS stuff.
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Babcock_Hall

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Re: Can someone help with this question?
« Reply #10 on: September 28, 2022, 08:38:10 AM »
@Babcock_Hall Do you think that making that assumption is a fair requirement for a High School student?

Can the question be answered? I feel it lacks something like "both reactants are completely consumed".
I think that when the question does not specify, it is fine to assume a complete reaction.
I think that the question would be improved by stating this outright, but I don't think that this assumption is beyond the means of a high school student.
« Last Edit: September 28, 2022, 12:00:49 PM by Babcock_Hall »

Corribus

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Re: Can someone help with this question?
« Reply #11 on: September 28, 2022, 09:33:35 AM »
I think questions in introductory chemistry courses always do well to spell out what assumptions students should be making to solve them - even if those assumptions are rather obvious or routine. Doing so serves as a good reminder to students that assumptions are always being made and sometimes we don't even realize it. Being aware of what assumptions you are making when forming a conclusion from experimental data is the foundation of sound science.
What men are poets who can speak of Jupiter if he were like a man, but if he is an immense spinning sphere of methane and ammonia must be silent?  - Richard P. Feynman