Chemistry: Post your doubts here!

[knowitall10]

oh okay,Thanku Very Much

no problem

 

[pearl angel]

no problem

could u please confirm me if the column headings in Q2(a) are:
mass of water(C-B)
mass of solid(D-C)
solubility(F/E) into 100
http://papers.xtremepapers.com/CIE/... AS Level/Chemistry (9701)/9701_s11_ms_52.pdf

 

[pearl angel]

could u please confirm me if the column headings in Q2(a) are:
mass of water(C-B)
mass of solid(D-C)
solubility(F/E) into 100
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_s11_ms_52.pdf

sorry
http://papers.xtremepapers.com/CIE/... AS Level/Chemistry (9701)/9701_s11_qp_52.pdf

 

[knowitall10]

look at the thread chem p5 tips..we were discussing it a few mins ago

 

[pearl angel]

look at the thread chem p5 tips..we were discussing it a few mins ago

i just checked it,im confused about the solubility part but other than that,we find the solid by subtracting ' (D) mass of boiling tube,water and solid' from ' (C) mass of boiling tube and water' OR we find solid by subtracting ' (E) mass of water' from ' (D) mass of boiling tube,water and solid' ?? please help me out i will be very grateful

 

[gary221]

i just checked it,im confused about the solubility part but other than that,we find the solid by subtracting ' (D) mass of boiling tube,water and solid' from ' (C) mass of boiling tube and water' OR we find solid by subtracting ' (E) mass of water' from ' (D) mass of boiling tube,water and solid' ?? please help me out i will be very grateful

mass of solid = D - C

 

[pearl angel]

mass of solid = D - C

thanx

 

[A star]

computing people join the thread https://www.xtremepapers.com/commun...9691-post-your-doubts-here.25670/#post-530873

 

[Ashique]

In questions such as these:
"Explain why barium sulphate is less soluble than calcium sulphate"

The ms says:
down the group: the ∆Hsolution becomes more endothermic;
both lattice energy and ∆Hhydration become less (exothermic);
due to ionic radius (of M2+) increasing;
but ∆Hhydration changes more than lattice energy


Can someone please explain this to me?

 

[darkfire]

• Use of the Data Booklet is relevant to this question.
  A sample of propyl ethanoate is hydrolysed by heating under reflux with aqueous sodium
  hydroxide. The two organic products of the hydrolysis are separated, purified and weighed.
  Out of the total mass of products obtained, what is the percentage by mass of each product?
  A 32.4 % and 67.6 %
  B 38.3 % and 61.7 %
  C 42.3 % and 57.7 %
  D 50.0 % and 50.0 %

Answer is C ... how?

 

[A3G]

how to prepare for the chemistry practical??

 

[A star]

how to prepare for the chemistry practical??

tell me when u get the answer to this never been answered before quedtion

 

[knowitall10]

• Use of the Data Booklet is relevant to this question.
  A sample of propyl ethanoate is hydrolysed by heating under reflux with aqueous sodium
  hydroxide. The two organic products of the hydrolysis are separated, purified and weighed.
  Out of the total mass of products obtained, what is the percentage by mass of each product?
  A 32.4 % and 67.6 %
  B 38.3 % and 61.7 %
  C 42.3 % and 57.7 %
  D 50.0 % and 50.0 %

Answer is C ... how?

Did u try it out yourself?

 

[sheeza]

can anyone help me with the presentation of data collected and the tables , how to make them , what should be in the table etc ?????

 

[A3G]

tell me when u get the answer to this never been answered before quedtion

https://www.xtremepapers.com/community/threads/tips-for-chemistry-practicals-p3.11810/ got it..

 

[knowitall10]

can anyone help me with the presentation of data collected and the tables , how to make them , what should be in the table etc ?????

Give me an example of what u mean..

 

[sheeza]

Give me an example of what u mean..

http://papers.xtremepapers.com/CIE/... AS Level/Chemistry (9701)/9701_w12_qp_34.pdf
like in Q2 )a) how to show the result ??

 

[knowitall10]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_w12_qp_34.pdf
like in Q2 )a) how to show the result ??

Make three columns each with one of the FB's and then record ur observations with each of the reagents u add. I'm sorry of my answer is a bit vague- i'm in A2, but i was pretty good with the tables.
I'm sorry once again..:/

 

[Bebeskii]

I need some tips for calculations. for example calculations for acid-alkaline experiment

 

[A star]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_w12_qp_34.pdf
like in Q2 )a) how to show the result ??

here add the labels