CHEM AND BIO HELP AND TIPS HERE

[$H00t!N& $t@r]

Thanks haris, now i understand the calculations part, however I dont quite understand why mg is the limiting reagent and how can we know if it has been used up? Other than this, you didnt answer how many moles of the other reagent (in this case ethanoic acid) are left unreacted.

By the way, do u knw any good websites on moles?

[LILDEEHARRISS]

hey
Can anyone or NID help me wit a question on may une 2009 chemistry- question 5b
Please help my exams are nxt week!

Thank you.

[nid404]

As soon as i'm back from school

[Vin]

hey how are we supposed to stdy for organic chemistry especially the structures for starch/carbs or Nylon n Terylene..(chemical reactions involved too)
so are v supposed to kno them by heart?? or jus no the idea..
hav these structures been asked in any past paper because i might hav missed them.
thnkx

[Ghost Of Highbury]

Yes the structures are asked hell lotta times in paper3. U have to study them "by heart".

[Vin]

okay thanks so they are basically asked in paper 3 right??
i hav a mini vacation before chemistry paper3 (10 days off!!) so tht might give me time to learn them properly
im strong with  the rest of organic tho..
thanks..

[K_M]

Cystic fibrosis is an inherited disease which affects the lungs and digestive system. It results from mutation in a gene responsible for making a protein which is involved in the transport of ions across cell boundaries.

The effect is to produce a sticky mucus which clogs the lungs and can lead to serious infection. A similar sticky mucus also blocks the pancreas (a part of the digestive system) which provides enzymes for breaking down food. This gets in the way of the processes which convert the food into molecules which can be absorbed by the body.

thank you soo much Nid! That really helped! =)

[Ghost Of Highbury]

okay thanks so they are basically asked in paper 3 right??
i hav a mini vacation before chemistry paper3 (10 days off!!) so tht might give me time to learn them properly
im strong with  the rest of organic tho..
thanks..

Ur welcome.

[haris94]

Thanks haris, now i understand the calculations part, however I dont quite understand why mg is the limiting reagent and how can we know if it has been used up? Other than this, you didnt answer how many moles of the other reagent (in this case ethanoic acid) are left unreacted.

By the way, do u knw any good websites on moles?

limiting reagent is the reactant which will be used up first (fewer number of moles), therefore causing the reaction to stop
in this case there r fewer moles of mg than ch3cooh. so mg will get used up and then since there is no more mg, reaction is stopped

as to the moles of ch3cooh, i hv written that out of 0.5 moles, 0.4 will be used. so the unreacted ch3cooh is 0.1 moles.

[$H00t!N& $t@r]

limiting reagent is the reactant which will be used up first (fewer number of moles), therefore causing the reaction to stop
in this case there r fewer moles of mg than ch3cooh. so mg will get used up and then since there is no more mg, reaction is stopped

as to the moles of ch3cooh, i hv written that out of 0.5 moles, 0.4 will be used. so the unreacted ch3cooh is 0.1 moles.

THANKS ALOT!! I totally understand it now!

[haris94]

anytime 

[nid404]

hey
Can anyone or NID help me wit a question on may une 2009 chemistry- question 5b
Please help my exams are nxt week!

Thank you.

post the paper up plz

[saywhatsaykobe]

Hey nid, can you please help me with question number 5c. The answer says it is a catalyst but I need an explanation.

I also need help on question number 6.

Thanks!!!



By the way, did u find some bio paper 6 notes???

[holtadit]

Hey nid, can you please help me with question number 5c. The answer says it is a catalyst but I need an explanation.

I also need help on question number 6.

Thanks!!!



By the way, did u find some bio paper 6 notes???

In the paper you attached what question do you need help in ?

[saywhatsaykobe]

My bad 5g and 6. Srry!!!