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No Name Face
Sep 27th, 2005, 01:40 AM
If so, can someone help me balance this equation:

K2Cr2O7 + H2SO4 + C2H5OH ----> Cr2(SO4)3 + K2SO4 + CH3COOH + H2O

I'd love you forever!

LUIS9
Sep 27th, 2005, 02:29 AM
I've given it a try, I hope my stoichiometry isnt as pathetic as it once was.

I think its:

K2Cr207+3H2SO4+2C2H50H---> Cr2(SO4)_3 +K2SO4+4CH3OOH+H20

I got 18 hydrogens for both sides 21 oxygens for both sides and 4 carbos on each side. Hope it works out, I think this should be it.:wavey: You can let me know if I was way off. But I took general chem 5 years ago. Are you in High school, wait until you take in college its a lot more fun.;) Orgo only gets better!:tape:

WorldWar24
Sep 27th, 2005, 02:47 AM
If so, can someone help me balance this equation:

K2Cr2O7 + H2SO4 + C2H5OH ----> Cr2(SO4)3 + K2SO4 + CH3COOH + H2O

I'd love you forever!

K2Cr2O7 + 4.H2SO4 + C2H5OH + 2 H+ + 2e- ----> Cr2(SO4)3 + K2SO4 + CH3COOH + 6.H2O

This looks too easy, so I'm thinking this cannot be right. If we knew what level/ purpose this is for, maybe we could help

LUIS9
Sep 27th, 2005, 02:50 AM
K2Cr2O7 + 4.H2SO4 + C2H5OH + 2 H+ + 2e- ----> Cr2(SO4)3 + K2SO4 + CH3COOH + 6.H2O

This looks too easy, so I'm thinking this cannot be right. If we knew what level/ purpose this is for, maybe we could help

Right I forgot the redox and oxidation values. No wonder I gave up being a biochem major. :tape:

Sam's Slave
Sep 27th, 2005, 02:54 AM
I've given it a try, I hope my stoichiometry isnt as pathetic as it once was.

I think its:

K2Cr207+3H2SO4+2C2H50H---> Cr2(SO4)_3 +K2SO4+4CH3OOH+H20

I got 18 hydrogens for both sides 21 oxygens for both sides and 4 carbos on each side. Hope it works out, I think this should be it.:wavey: You can let me know if I was way off. But I took general chem 5 years ago. Are you in High school, wait until you take in college its a lot more fun.;) Orgo only gets better!:tape:

wrong :wavey:

Sam's Slave
Sep 27th, 2005, 02:55 AM
K2Cr2O7 + 4.H2SO4 + C2H5OH + 2 H+ + 2e- ----> Cr2(SO4)3 + K2SO4 + CH3COOH + 6.H2O

This looks too easy, so I'm thinking this cannot be right. If we knew what level/ purpose this is for, maybe we could help

there are free electrons in your formula so it isn't finished yet

LUIS9
Sep 27th, 2005, 02:56 AM
yup I forgot the ions and electrons, man do I feel old. I guess I became adversed to electrons after organic chem, too much of something can turn you against it, orgo is all about the flow of electrons. Darn it and I got a decent score on the MCAT and its of no use to me. :haha: :tape:

Sam's Slave
Sep 27th, 2005, 02:58 AM

trust my i'm a chemical technician ;)

K2Cr2O7 + H2SO4 + C2H5OH ----> Cr2(SO4)3 + K2SO4 + CH3COOH + H2O
________________________________________________

Red.: Cr2O7(2-) + 14 H(+) + 6 e(-)----> 7 H2O + 2 Cr(3+)
Ox.: C2H5OH ----> CH3CHO + 2 H(+) + 2e(-) |*3
______________________________________________
Cr2O7(2-) + 14 H(+) + 3 C2H5OH ----> 7 H2O + 2 Cr(3+) + 3 CH3CHO + 6 H(+)

Cr2O7(2-) + 8 H(+) + 3 C2H5OH ----> 7 H2O + 2 Cr(3+) + 3 CH3CHO
__________________________________________________ _
K2Cr2O7 + 4 H2SO4 + 3 C2H5OH ----> 7 H2O + Cr2(SO4)3 + 3 CH3CHO + K2SO4

ampers&
Sep 27th, 2005, 03:00 AM
wow...you all are making me feel so stupid right now.
ME F:retard: :tape:

Sam's Slave
Sep 27th, 2005, 03:02 AM
wow...you all are making me feel so stupid right now.
ME F:retard: :tape:

no just i made you look stupid , because mine is the right answer :p

nah don't worry....you know other stuff, stuff that is more import :hehehe:

ampers&
Sep 27th, 2005, 03:03 AM
no just i made you look stupid , because mine is the right answer :p

nah don't worry....you know other stuff, stuff that is more import :hehehe:
really? :hehehe:
like what? :angel:

LUIS9
Sep 27th, 2005, 03:05 AM
no just i made you look stupid , because mine is the right answer :p

nah don't worry....you know other stuff, stuff that is more import :hehehe:

What are you talking about chemistry is pretty much the biggest industry in which most developed nations rely on to keep their respective economies going.

Chemical engineers still top the salary charts right after college for BA OR BS holders. Not that other fields arent as important or useful but chem is the shit despite it being so abstract.

Sam's Slave
Sep 27th, 2005, 03:07 AM
What are you talking about chemistry is pretty much the biggest industry in which most developed nations rely on to keep their respective economies going.

Chemical engineers still top the salary charts right after college for BA OR BS holders. Not that other fields arent as important or useful but chem is the shit despite it being so abstract.

that was a joke. it was just an indirectness to miching's kinkiness ;)

WorldWar24
Sep 27th, 2005, 03:37 AM
erm Slave, the product of his reaction is CH3COOH not CH3CHO. MAybe he made a mistake there coz I tried with CH3COOH and the results were screwed up completely

Sam's Slave
Sep 27th, 2005, 03:57 AM
erm Slave, the product of his reaction is CH3COOH not CH3CHO. MAybe he made a mistake there coz I tried with CH3COOH and the results were screwed up completely

lol i didn't recognize that....but it has to be CH3CHO when you but these educts together. so i guess you're right and no name face made a mistake

K-Dog
Sep 27th, 2005, 04:28 AM
I have an AP Chem test tomorrow on net ionic equations and solution stoich and now u all, especially Sveta Slave, made me really nervous tomorrow. Part of our test involves oxidation and reduction (LEO says GER). I have a lot of studying to do tonight.

No Name Face
Sep 27th, 2005, 04:29 AM
no...i didn't make a typo...but i actually figured out the answer anyway, it took forever though. but if you really wanna help me out...here's the 2nd part to that question:

During a Breathalyzer Test it was determined that 1.9mg of K2Cr2O7 was consumed by the above reaction. Calculate the number of milligrams of ethanol in the test sample.

My lab manual says calculate the number of millimoles of potassium dichromate consumed by the ethanol in the test sample. Using the # of millimoles of dichromate consumed, stoichiometrically calculate the number of millimoles of ethanol. Express the final concentration in milligrams of ethanol.

BTW the answer to the first part was 2 K2Cr2O2 + 8 H2SO4 + 3 C2H5OH ----> 2 Cr2(SO4)3 + 2 K2SO4 + 3 CH3COOH + 11 H2O

btw you all get good reps for helping me out. thanks so much. :)

LUIS9
Sep 27th, 2005, 04:32 AM
I have an AP Chem test tomorrow on net ionic equations and solution stoich and now u all, especially Sveta Slave, made me really nervous tomorrow. Part of our test involves oxidation and reduction (LEO says GER). I have a lot of studying to do tonight.

Oh ap chem dont sweat it, if you end up going into careers where chem is required you probably will have to take general chem any ways again in college. If you do get a 5 on the ap test and really love chem, and would want to spare yourself of taking general chem, and hopping right into organic chem, then by all means suit your self. However, the wise choice would be to go with the freshmen honors general chem or just take it over again, its always a different experience and its a totally different ball park in college.

No Name Face
Sep 27th, 2005, 04:35 AM
Oh ap chem dont sweat it, if you end up going into careers where chem is required you probably will have to take general chem any ways again in college. If you do get a 5 on the ap test and really love chem, and would want to spare yourself of taking general chem, and hopping right into organic chem, then by all means suit your self. However, the wise choice would be to go with the freshmen honors general chem or just take it over again, its always a different experience and its a totally different ball park in college.

you are right.

btw - background info: i'm 19, taking general chem in college and these problems suck. :sad:

!!!--Duiz™--!!!
Sep 27th, 2005, 04:40 AM
I hate chemistry... can work so much better with particle physics...

K-Dog
Sep 27th, 2005, 04:41 AM
Oh ap chem dont sweat it, if you end up going into careers where chem is required you probably will have to take general chem any ways again in college. If you do get a 5 on the ap test and really love chem, and would want to spare yourself of taking general chem, and hopping right into organic chem, then by all means suit your self. However, the wise choice would be to go with the freshmen honors general chem or just take it over again, its always a different experience and its a totally different ball park in college.

I don't think I'm going to get an A in the class anyway, but i want to be a doctor, so me doing well in this class is important to me. Last year we had a teacher that taught general chem in a very childish way. She really dumbed it down for us, but didn't suceed in teaching it well. Stoich is a little fuzzy to me at the moment still, and the guy who teaches it thinks we all took his chemistry last year, when some of us didn't. He assumes a lot of stuff that some of us just don't know because we were never taught it. I have a 3.9 in my class from frosh to junior year, so I think I'll get into Wisconsin-Madsion, but I put pressure on myself to aways do well.

LUIS9
Sep 27th, 2005, 04:42 AM
you are right.

btw - background info: i'm 19, taking general chem in college and these problems suck. :sad:

What text are you using, let me guess Zumdhal? eeeelk yuck. Chemistry blows, it was only fun in high school. Polyprotic chemistry is really when you'l love this crap. These equilibrium problems can get out of proportion, you've not only got to solve a systems of linear equations but solve for a quadratic equation while balacing the whole shit. Despite getting a c and a c- in orgo I'd much rather take organic again then general chem.

LUIS9
Sep 27th, 2005, 04:49 AM
I don't think I'm going to get an A in the class anyway, but i want to be a doctor, so me doing well in this class is important to me. Last year we had a teacher that taught general chem in a very childish way. She really dumbed it down for us, but didn't suceed in teaching it well. Stoich is a little fuzzy to me at the moment still, and the guy who teaches it thinks we all took his chemistry last year, when some of us didn't. He assumes a lot of stuff that some of us just don't know because we were never taught it. I have a 3.9 in my class from frosh to junior year, so I think I'll get into Wisconsin-Madsion, but I put pressure on myself to aways do well.

Oh see thats what I meant you will happen to learn to love chemistry regardless of your true feelings for the subject. Cause Medicine as much as I thought it wasnt about chemistry is all about chemistry, I mean all the prescription drugs are based on these lame topics we learn in general chem, equilibrium, redox reactions, solutions, stoichiometry that silly little word will stick in my head for years to come. You will probably have to take organic, and biochem for med school, you will see biochem for another year in med school. Wow Wisconsin is a great school. Your SAT's must be in the upper 1400's I guess. Yup if you really want to get a taste of what college is like, have your high school professors challenge you. Not one single ap course can prepare you for college unless you've decided to really challenge your self.

K-Dog
Sep 27th, 2005, 04:58 AM
Oh see thats what I meant you will happen to learn to love chemistry regardless of your true feelings for the subject. Cause Medicine as much as I thought it wasnt about chemistry is all about chemistry, I mean all the prescription drugs are based on these lame topics we learn in general chem, equilibrium, redox reactions, solutions, stoichiometry that silly little word will stick in my head for years to come. You will probably have to take organic, and biochem for med school, you will see biochem for another year in med school. Wow Wisconsin is a great school. Your SAT's must be in the upper 1400's I guess. Yup if you really want to get a taste of what college is like, have your high school professors challenge you. Not one single ap course can prepare you for college unless you've decided to really challenge your self.

I took the ACT, and lets say that I won't be counting on that score to get me in (I got a 25, which is right in the middle half at Madison). My mom is a pharmacist who graduated from Wisconsin herself, and she told me about how much chemistry is involved. I know I'll take chem again, but I want to reunderstand it the way I used to. I forgot a lot of the summer. Not to mention I have 3 other AP's (Calc, English, and Spanish) and other hard elective classes. I know how important it is to take a hard senior schedule to impress the colleges. I will count on my GPA, extracurriculars, leadership forum in DC for 6 days last year, and both parents as graduates of Wisconsin to get me in to UW. I want to challenge myself this year to better prepare for college freshman year. Those who take easy senior years, struggle freshman year. I also want to know as much I can before I go to college. So from 4 am-6:15am, I'll be studying AP Chem for tomorrow. Hopefully the test goes okay. My teacher is nice and gives us review questions that are just like the test questions to work on.

No Name Face
Sep 27th, 2005, 04:59 AM
What text are you using, let me guess Zumdhal? eeeelk yuck. Chemistry blows, it was only fun in high school. Polyprotic chemistry is really when you'l love this crap. These equilibrium problems can get out of proportion, you've not only got to solve a systems of linear equations but solve for a quadratic equation while balacing the whole shit. Despite getting a c and a c- in orgo I'd much rather take organic again then general chem.

not that book but probably one thats just as annoying.

LUIS9
Sep 27th, 2005, 05:08 AM
I took the ACT, and lets say that I won't be counting on that score to get me in (I got a 25, which is right in the middle half at Madison). My mom is a pharmacist who graduated from Wisconsin herself, and she told me about how much chemistry is involved. I know I'll take chem again, but I want to reunderstand it the way I used to. I forgot a lot of the summer. Not to mention I have 3 other AP's (Calc, English, and Spanish) and other hard elective classes. I know how important it is to take a hard senior schedule to impress the colleges. I will count on my GPA, extracurriculars, leadership forum in DC for 6 days last year, and both parents as graduates of Wisconsin to get me in to UW. I want to challenge myself this year to better prepare for college freshman year. Those who take easy senior years, struggle freshman year. I also want to know as much I can before I go to college. So from 4 am-6:15am, I'll be studying AP Chem for tomorrow. Hopefully the test goes okay. My teacher is nice and gives us review questions that are just like the test questions to work on.

Oh wow its never a wise choice to take more than 2 ap courses in one year, It happened to me too, I took 4 ap classes my high school senior year, Ap English lit, oh my God I so got a two solely based on my free response on Hamlet I can guarantee that. Ap calculus and ap bio as well as ap macro-economics were the others, its just not wise, not even wise peeps take 3 science courses in college the same semester unless they have to. College is more about giving priorities to whats really important to you and your major. Time management skills, discipline and hard work is what will get you through college with a lot of positives. Theres no such thing as I am smarter in college any longer, theres always a smarter cat than you in college, especially when you go to any of the top 30 research universities in the country, of course you can have an IQ of 160+, but thats pretty rare.

LUIS9
Sep 27th, 2005, 05:12 AM
not that book but probably one thats just as annoying.

Awww sorry about that, I am sure he'l come to the rescue and hopefully before you have class. He/she really knows what they're talking about certainly in the chemistry department. I wish I could help but its been much too long since I took chem and it wasnt my forte by any means. :tape:

K-Dog
Sep 27th, 2005, 05:15 AM
Oh wow its never a wise choice to take more than 2 ap courses in one year, It happened to me too, I took 4 ap classes my high school senior year, Ap English lit, oh my God I so got a two solely based on my free response on Hamlet I can guarantee that. Ap calculus and ap bio as well as ap macro-economics were the others, its just not wise, not even wise peeps take 3 science courses in college the same semester unless they have to. College is more about giving priorities to whats really important to you and your major. Time management skills, discipline and hard work is what will get you through college with a lot of positives. Theres no such thing as I am smarter in college any longer, theres always a smarter cat than you in college, especially when you go to any of the top 30 research universities in the country, of course you can have an IQ of 160+, but thats pretty rare.

The reason I'm taking 4 is because of this: I took honors english for 3 years and it would look stupid if I didn't take AP lang because AP lit didn't get any interest; I was in spanish 4 last year and I love our spanish 5 teacher so of course why wouldn't I take spanish 5; I took honors pre-calc to take AP Calc so i could get some college calc out of the way. This year sux big time. I don't get any sleep and I have 7 tough courses. Next semester should be better with senior health and a study hall.

Here's my terrible schedule:

Geography
AP Chem
AP Lang
Physics
2 World Wars
AP Calc
AP Spanish

Next semester geography and 2 World Wars are replaced with the above mentioned class. This year is tough, but I'll deal with it.

LUIS9
Sep 27th, 2005, 05:26 AM
The reason I'm taking 4 is because of this: I took honors english for 3 years and it would look stupid if I didn't take AP lang because AP lit didn't get any interest; I was in spanish 4 last year and I love our spanish 5 teacher so of course why wouldn't I take spanish 5; I took honors pre-calc to take AP Calc so i could get some college calc out of the way. This year sux big time. I don't get any sleep and I have 7 tough courses. Next semester should be better with senior health and a study hall.

Here's my terrible schedule:

Geography
AP Chem
AP Lang
Physics
2 World Wars
AP Calc
AP Spanish

Next semester geography and 2 World Wars are replaced with the above mentioned class. This year is tough, but I'll deal with it.

May God bless your poor soul, I am not being sarcastic, I know what a heavy schedule that is, to top it off you're taking physics too. Jesus Christ, may the lord have mercy. Well I am so glad you're taking ap spanish, its my native language so yeah, way to go :yeah: . Its really a great language I know the grammar can get fishy, especially the subjunctive and the plus que parfait, like it is for french. Oh I forgot the nasty imperfect too, why did grammar have to exist, I hate grammar, but spanish grammar came naturally to me, because my parents always spoke to me in the language.

Por cierto, te deseo la mejor de la suerte, luego me contaras como te fue al final de este semestre y como te fue en tus examenes al fin de ano. Que estes bien!:wavey:

K-Dog
Sep 27th, 2005, 05:36 AM
May God bless your poor soul, I am not being sarcastic, I know what a heavy schedule that is, to top it off you're taking physics too. Jesus Christ, may the lord have mercy. Well I am so glad you're taking ap spanish, its my native language so yeah, way to go :yeah: . Its really a great language I know the grammar can get fishy, especially the subjunctive and the plus que parfait, like it is for french. Oh I forgot the nasty imperfect too, why did grammar have to exist, I hate grammar, but spanish grammar came naturally to me, because my parents always spoke to me in the language.

Por cierto, te deseo la mejor de la suerte, luego me contaras como te fue al final de este semestre y como te fue en tus examenes al fin de ano. Que estes bien!:wavey:

Gracias senor/a!!! Espanol es muy facil este ano porque mi profesora de espanol 4 sea muy dificil, pero me ayudo con espanol este ano. La clase de fisica es muy facil a mi colegio. El profesor no es muy inteligente en mi opinion. Tenemos un projecto al fin del ano y voy a hacer el projecto en tenis, mi deporte favorito!!

Enough spanish!! If my grammar or conjegation is bad, LO SIENTO!! The thing that is going to bug me is the irregular nouns on the AP test. There are a lot and I don't like them at all!! Next semester should be fine, and my stress will go down with only 5 classes really. Thanks for all the support!!

middy
Sep 27th, 2005, 02:15 PM
no...i didn't make a typo...but i actually figured out the answer anyway, it took forever though. but if you really wanna help me out...here's the 2nd part to that question:

During a Breathalyzer Test it was determined that 1.9mg of K2Cr2O7 was consumed by the above reaction. Calculate the number of milligrams of ethanol in the test sample.

My lab manual says calculate the number of millimoles of potassium dichromate consumed by the ethanol in the test sample. Using the # of millimoles of dichromate consumed, stoichiometrically calculate the number of millimoles of ethanol. Express the final concentration in milligrams of ethanol.

BTW the answer to the first part was 2 K2Cr2O2 + 8 H2SO4 + 3 C2H5OH ----> 2 Cr2(SO4)3 + 2 K2SO4 + 3 CH3COOH + 11 H2O

btw you all get good reps for helping me out. thanks so much. :)

:wavey: I got 0.446mg C2H5OH I think thats right

Chunchun
Sep 27th, 2005, 04:16 PM
awww. Chemistry sucks :armed: It's always my worst subject :banghead: