Chemistry: Post your doubts here!

[A*****]

well in dehydration, the water is not chemically bonded to a compound. Dehydration is something like this:
CuSO4.5H2O -----> CuSO4 + 5H2O

But see our book says that this reaction IS dehydration

 

[Hajera]

i dont understand how do u know which ones are identical and which are optical isomers.
how to solve parts (ii) and (iii)?

 

[anastasia grey113]

View attachment 63436
i dont understand how do u know which ones are identical and which are optical isomers.
how to solve parts (ii) and (iii)?

Holmes

 

[anastasia grey113]

But see our book says that this reaction IS dehydration

well thaz partly y our teacher dint get us to do organic from the book
v always learned it as dehydration cuz of the reason i gave
n now uk wut the correct term is right? so just go with elimination
elimination means turning something into an alkene
halogenoalkanes also go thru elimination for instance...but no H2O is produced
just think of elimination as a better word

 

[Holmes]

View attachment 63436
i dont understand how do u know which ones are identical and which are optical isomers.
how to solve parts (ii) and (iii)?

Holmes

I recently asked this question too and this is what anastasia grey113 came up with:
https://www.xtremepapers.com/commun...st-your-doubts-here.9859/page-860#post-992786

 

[Hajera]

I solved it a few minutes ago and I thought of the exact same method xD. I was hoping for a less time-consuming method so I didn't mention it. But thanks anyway Holmes and anastasia grey113

 

[amina1300]

is this correct ? P5 specimen paper 2016

 

[amina1300]

ignore the point at 3.8

 

[anastasia grey113]

View attachment 63446
is this correct ? P5 specimen paper 2016

yes its correct

 

[furuta]

yes its correct

but there aren’t equal points on both sides tho..? Isn’t that imp to consider for a best fit line?

 

[MIK3Y.]

Hey I need help with (ii).

 

[Mohammed alomary]

Does anyone have or know where to get February march papers . 2018 papers AS

 

[A*****]

Does anyone have or know where to get February march papers . 2018 papers AS

I've searched everywhere but they aren't available yet

 

[amina1300]

9701_s15_qp_51 Q1 part vii

 

[Dipim007]

Just Divide 150 By 114.3(Mr of Mg(hcoo)^2 ) to get answer....

 

[amina1300]

Just Divide 150 By 114.3(Mr of Mg(hcoo)^2 ) to get answer....

150? The question specifically says use your answers from part vi and that has and answer os 0.051

 

[Minsa Fatima]

150? The question specifically says use your answers from part vi and that has and answer os 0.051

2 mol Mg+2 reacts with 1 mol HCoo- so 0.051/2
initial conc 50 times the diluted so *50

 

[Krisarmy]

Hey some questions in p5 asked for half equations but we are not provided with data booklet...are we supposed to memorize them?

 

[Minsa Fatima]

Hey some questions in p5 asked for half equations but we are not provided with data booklet...are we supposed to memorize them?

we need to work them out using the info given

 

[furuta]

hii any predictions for chem p5 tmrw??? ):