Chemistry: Post your doubts here!

[Soulgamer]

really thank u sooo much..this is so appreciated

No problemo!

 

[Soulgamer]

Are you kidding me?.Chemistry is AWESOME!..

Chemistry seems boring at first but once you get to know the concepts and stuff, theres this euphoric feeling I cant explain
Its awesom-tas-tic!

 

[angelicsuccubus]

Are you kidding me?.Chemistry is AWESOME!..

no dont get me wrong, I love chem... but studying when you feel like you're re reading a story is boring.. and I hate studying by myself

 

[angelicsuccubus]

tell me something...when we are finding the oxidation numbers of elements in compounds in an equation... do we take the number of molecules in account? Like 2NH3 .. would I take the 2 in account?

 

[Amy Bloom]

Yeah, it's 24 dm^3 per mole, and 1 mole of O2 is 32 g. So basically, 24 dm^3 = 32 g of oxygen at room temperature which is what I did in my calculation. I have always used grams to solve these type of questions and I never get the answer wrong.. I'd be surprised if the examiners wouldn't accept this method..

If u are at ease with working in grams then keep doing so. Try to work in moles from time to time, you never know. ^^

 

[ibadsiddiqi]

tell me something...when we are finding the oxidation numbers of elements in compounds in an equation... do we take the number of molecules in account? Like 2NH3 .. would I take the 2 in account?

no you dont..

 

[angelicsuccubus]

no you dont..

merci

 

[ibadsiddiqi]

Chemistry seems boring at first but once you get to know the concepts and stuff, theres this euphoric feeling I cant explain
Its awesom-tas-tic!

Ikr!..The feelings amazing when you know a lot of stuff and can explain it to other people!

 

[ibadsiddiqi]

merci

votre accueil!

 

[angelicsuccubus]

votre accueil!

LOL! votre accueil is out of context... what you just said basically means your (as in something that belongs to me) and welcome! (as in welcome to this place) ... what you're supposed to say is "de rien"

 

[ibadsiddiqi]

LOL! votre accueil is out of context... what you just said basically means your (as in something that belongs to me) and welcome! (as in welcome to this place) ... what you're supposed to say is "de rien"

oh..well this is embarrassing!..You know french?..or is it translate.google.com?..

 

[angelicsuccubus]

oh..well this is embarrassing!..You know french?..or is it translate.google.com?..

lol its okay .. translation websites are not intelligent so I can forgive you. And I studied french in from gr6-8 then gave the french IGCSE .. =]

 

[ibadsiddiqi]

lol its okay .. translation websites are not intelligent so I can forgive you. And I studied french in from gr6-8 then gave the french IGCSE .. =]

oh nice!..im impressed!

 

[angelicsuccubus]

oh nice!..im impressed!

-_- we should shutup, this is a chem thread..

are you doing A2 chem too? cause I don't like the section B chapters in my text book.

 

[shan5674]

http://www.xtremepapers.com/papers/... AS Level/Chemistry (9701)/9701_w09_qp_21.pdf

can someone pls tell me how do you know the product in q5 b(iii) "identify J" and how to draw the structural formula in c

Thanks

 

[ibadsiddiqi]

-_- we should shutup, this is a chem thread..

are you doing A2 chem too? cause I don't like the section B chapters in my text book.

Well i am going to do that next year!....but its supposed to be easy

 

[angelicsuccubus]

Well i am going to do that next year!....but its supposed to be easy

you're gonna like it ... but its reallllllly long and I should study it now.. cause I have my m2 exam the day before it and I really need to do well on that.

 

[Noyb Lol]

thanks so much!!

 

[angelicsuccubus]

http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_w09_qp_21.pdf

can someone pls tell me how do you know the product in q5 b(iii) "identify J" and how to draw the structural formula in c

Thanks

Here, I wrote it just how I thought it.. .
https://www.dropbox.com/s/oqs22luv6wut9nt/IMAG0285.jpg

Edit: J is wrong, it should be CH3CH(OH)COOH [you know this cause the empirical formula is CH2O ]

 

[ibadsiddiqi]

Here, I wrote it just how I thought it.. .
https://www.dropbox.com/s/oqs22luv6wut9nt/IMAG0285.jpg

Your J is wrong. There are 3 carbon atoms so hence there should 3 oxygen atoms. The structural formula wud be CH3CH(OH)COOH.