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Chemistry: Post your doubts here!

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Hey please help question b)
I'm quite sure Ecell = Ereduction - Eoxidation
then it becomes -0.83-1.23 = -2.86V and -0.83 -1.36 = -2.19V

However the ms says +2.86V and +2.19V
why is it so?

does Ecell becomes reversed for electrolysis?
 

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How do we know from the structure the compund is 1 4 di substituded arene as ms says???please reply ASAP
 

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This will lead us no where. Never has an endorsed chemistry book mentioned carbonic acid nor do we need to know about its chemistry. Like I said, chances of you having carbonic acid in your mouth are slim to none. (the reaction is very slow and you need an enzyme to make CO2 react with H2O).
Therefore, by intuitively considering the basic mineral and organic acids we come across in our course, 3 is not true.

So unless you come up with a more valid point to defend the flimsy carbonic acid argument, any discussion will be futile.
I still don't understand why you choose to defend you "biological" explanation. I thought the question was about equilibria, but instead of explaining in those terms you choose to do it a totally different way i.e "chemistry doesn't apply here, this is all biology". If that is the case I would sit in my chemistry exam with the chapter 'anatomy of the heart' prepared, or maybe even 'the formula for the coefficient of friction' prepared.
If you can't explain that question in simple terms, without relating to some chapter in your 'endorsed' biology book which your examiner is apparently examining you from, then I'm afraid you are right: this discussion is pointless, unless you can explain it in other terms.
And I am at a loss at explaining why you don't know what carbonic acid is, there are only a handful of acids we ever come across in our course, and surely you must have heard the name.
And why would you go off and call somebody's argument 'flimsy' just because you are trying to defend a totally baseless claim that the examiners will test you on something you are not expected to know?
You don't need answer that question now, it's apparent you don't have a valid argument.
 
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Number of gas moles on the left hand side is 1.
Number of gas moles on the right hand side is 2.
Increasing the pressure favors backward reaction (so yield of propan-2-ol increases, yield of propanone and hydrogen decreases)

i guess tht explains my doubt....... thxx a lot :)
 
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B is right because all of the other 3 diagrams are wrong. In A, the bond length increases because the bond energies decrease. In C, the B.P increases with increasing # of electrons. And D is wrong because the HX energies decrease (you can even check this in the data booklet).

...

And B is right because the # of Van Der Waal forces increase with increasing electrons.
 

Jaf

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I still don't understand why you choose to defend you "biological" explanation. I thought the question was about equilibria, but instead of explaining in those terms you choose to do it a totally different way i.e "chemistry doesn't apply here, this is all biology". If that is the case I would sit in my chemistry exam with the chapter 'anatomy of the heart' prepared, or maybe even 'the formula for the coefficient of friction' prepared.
If you can't explain that question in simple terms, without relating to some chapter in your 'endorsed' biology book which your examiner is apparently examining you from, then I'm afraid you are right: this discussion is pointless, unless you can explain it in other terms.
And I am at a loss at explaining why you don't know what carbonic acid is, there are only a handful of acids we ever come across in our course, and surely you must have heard the name.
And why would you go off and call somebody's argument 'flimsy' just because you are trying to defend a totally baseless claim that the examiners will test you on something you are not expected to know?
You don't need answer that question now, it's apparent you don't have a valid argument.
So we'll just have to agree to disagree. That's fine.
 
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I am not sure if this is the right way to solve it, but I got the right answer with it so..

C6H12 + 9O2 -> 6CO2 + 6H2O

So you have 6 moles of CO2 and 6 moles of H2O. P will absorb all of the mass of H2O, while Q will absorb of all of the mass of CO2. Their masses are 6(18) and 6(44) respectively, and the ratio will give you 18/44 = 0.41.
 
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HOW DO YOU KNOW IF A MOLECULE IS PLANAR OR NOT??? eg:for CO2, PCL5, ethane, ethene, NH3 (AS)




REPLY PLZ!
 
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Yeah, you are right. Actually, my teacher told me that 3 bonds and 1 lone pair are approximately 107, and since B and C were quite close to each other I thought C would be correct. Confusing question IMO.
 
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