Indigo_Child22
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Lost with these problems....
I was doing fairly well in chemistry this semester until some health problems kept me out of class for two weeks....now I am totally lost and
desperately need help. I have 6 problems due tomorrow all like the following. I am usually pretty good at figuring this sort of thing out on my own,
but I can not find a problem like this in my text that is broken down and done step by step. I have no idea where to even begin.
"Ordinary chalkboard is a solid mixture, with limestone (CaCO3) and gypsum (CaSO4) as its principal ingredients. Limestone dissolves in dilute HCL(aq)
but gypsum dies not according to the following unbalanced reaction:
CaCO3(s) + HCL(aq) -----> CaCl2(aq) + CO2(g) + H2O(l)
(a.) If a 12.3g piece of chalk that is 69.7% CaCO3 is dissolved in excess HCL(aq), what mass of CO2(g) will be produced?
(b.) Determine the mass percent of CaCO3 in a 4.38g piece of chalk that yields 1.31.g CO2 when it reacts with excess HCL(aq)
I guess what I am looking for is someone to show me how this would be done step by step, then, hopefully, I can apply it to the other 5...
(I realize that I am asking for someone to do part of my homework for me and I suspect this is probably frowned upon here, and I do feel bad about it,
but I desperately need help...)
Thanks.
Tim.
[Edited on 24-10-2010 by Indigo_Child22]
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Magpie
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Quote: Originally posted by Indigo_Child22  |
I guess what I am looking for is someone to show me how this would be done step by step, then, hopefully, I can apply it to the other 5...
Tim.
[Edited on 24-10-2010 by Indigo_Child22] |
The reactants and products will be proportional to the molecular weight times the number of molecules in a balanced equation. This is a general
statement.
If I showed how to work the problem step-by-step you'd likely get your homework done, but I don't know if you would have learned anything about
chemistry. It would be like "block and copy," or as we said in my day "plug and crank."
The single most important condition for a successful synthesis is good mixing - Nicodem
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chemrox
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Go to your college counselor and buy some more time. It's essential to learn stoichiometry early on. It will help you throughout your life. This is
the most important course you will ever take. As in it you will learn how to think through any problem.
"When you let the dumbasses vote you end up with populism followed by autocracy and getting back is a bitch." Plato (sort of)
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Indigo_Child22
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I understand where you all are coming from, but understand that had I been in class, that is how he would have taught it....He may not be the best
professor in the world but atleast I would have some idea of where to start this kind of thing.
With that said I think I may have figured out part a, perhaps one of you guys would be so kind as to tell me if I am correct: 3.77g CO2 produced?
Thanks again.
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Indigo_Child22
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and 68.01% for part b?
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Magpie
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You got it!
The single most important condition for a successful synthesis is good mixing - Nicodem
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Indigo_Child22
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Excellent! Thanks for the push guys!
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