Chemistry: Post your doubts here!

[Musab100]

All those saying the paper was shit easy
Agreed
BUT
it was trickier than most people here think it was
I can bet my life most people got the Electrode Potential Wrong
Seemed simple I know
Wasnt exactly what it seemed.
I could go on and on about the various small stuff in the paper which people are presuming to be easy and werent exactly straightforward but paper discussion is not allowed
Secondly
Grade Thresholds dont vary much. Difficult papers have grade thresholds around 62 for paper 4. Medium Difficulty is 65. All those saying grade threshold will be 76-77 for this paper have got to be shitting me
It was easy, agreed but its not like everyone around the world is just a fcking brilliant super genius all of a sudden this year. If grade thresholds were that variable, then they should fall to around 52 during difficult papers which they do not.
The person who said grade threshold for A* will be somewhere around 230?
lol
Generally the grade threshold for an A* is say around 200. Easy papers? Goes up to at max, at max 210. Thats it.
230/260 is unrealistic.

i completely agree with you

 

[BeBeskii108]

What are indicators that can be both used to identify acid and alkaline ?

 

[BeBeskii108]

Another question. How do you find Slope of the graph in paper 5. Is it like finding a gradient ? if so Can I choose random 2 points ? How do I draw the construction lines ?

 

[omarjaved619]

Ok so in a Paper 5 , in a planning question, they asked us to mention how we would dry the precipitate. In the Answer scheme, the gave a few methods along with "NOT heat or the use of a Bunsen..."

The next question asked how we would ensure the precipitate was thoroughly dried. The answer went like
"The drying process should be repeated to constant mass . ALLOW HEAT/REHEAT to constant mass/weight."

What is this cwap?

 

[omarjaved619]

Another question. How do you find Slope of the graph in paper 5. Is it like finding a gradient ? if so Can I choose random 2 points ? How do I draw the construction lines ?

Yes. Slope is the gradient. You can choose any two points which are sufficiently apart. The construction lines are just a big triangle against the line. Kinda like this https://www.google.com/search?q=fin...gebra%2FStraightLinesin2D%2FSlope.htm;707;453

 

[Snowysangel]

It says in he examiners report that removing ammonia in the harbor process STOPS the backward reaction? Wth I thought both reactions always occur...just that one of them proceeds at a faster rate ie the rate if reaction increases. What does the position if equilibrium mean exactly? That the yield of either the backward or forward reaction increases...I know..but HOW?

 

[Someone2]

Ok so in a Paper 5 , in a planning question, they asked us to mention how we would dry the precipitate. In the Answer scheme, the gave a few methods along with "NOT heat or the use of a Bunsen..."

The next question asked how we would ensure the precipitate was thoroughly dried. The answer went like
"The drying process should be repeated to constant mass . ALLOW HEAT/REHEAT to constant mass/weight."

What is this cwap?

lol i just know that an OVEN is used to dry the precipitate. The constant mass shows that now only the solid is left-all solvent that was adding to the mass is removed.

n yes... paper 5 chem is crap

 

[BeBeskii108]

Yes. Slope is the gradient. You can choose any two points which are sufficiently apart. The construction lines are just a big triangle against the line. Kinda like this https://www.google.com/search?q=find gradient construction lines&client=aff-maxthon-maxthon4&channel=t26&source=lnms&tbm=isch&sa=X&ei=io90U_1Th7S4BPqzgvgG&ved=0CAgQ_AUoAQ&biw=1367&bih=606#facrc=_&imgdii=_&imgrc=q3QY7oC0nNKu_M%3A;5cZQbj0PR8XOYM;http%3A%2F%2Fmathsfirst.massey.ac.nz%2FAlgebra%2FStraightLinesin2D%2Fimages%2Fslope1.gif;http%3A%2F%2Fmathsfirst.massey.ac.nz%2FAlgebra%2FStraightLinesin2D%2FSlope.htm;707;453

Thank you

 

[BeBeskii108]

AAAA I'm worried about my Paper 5. Paper 4 was not easy. So I have to try my best but Paper 5 is difficult.

 

[omarjaved619]

AAAA I'm worried about my Paper 5. Paper 4 was not easy. So I have to try my best but Paper 5 is difficult.

Have faith! All I'll suggest is do as many past papers as you can.

 

[saadgujjar]

http://papers.xtremepapers.com/CIE/... AS Level/Chemistry (9701)/9701_s10_qp_52.pdf
q1 c diagram needed

 

[Snowysangel]

Guys post your paper 1 doubts here : https://www.xtremepapers.com/community/threads/chemistry-and-physics-mcqs.33811/

 

[Abdulaziz T]

Guys, I'm really bad in question no.1 experiments in Chem paper 5.. Can anyone give me tips or anything ?

 

[zackle09]

http://papers.xtremepapers.com/CIE/...d AS Level/Chemistry (9701)/9701_s09_qp_5.pdf

can someone please tell me how to plot the graph for question 2!!

 

[Snowysangel]

Could some one explain. This to me!

 

[YetAnotherCandy]

http://papers.xtremepapers.com/CIE/... AS Level/Chemistry (9701)/9701_w13_qp_51.pdf
^^Q1, help needed in calculation, part (d)(iv)

 

[Snowysangel]

Which if the following is the strongest reducing agent?
A Cl-
B Ar
C K+
D Ca 2+
E Al3+
Can someone please answer!! Suchal Riaz GCE As and a level

 

[Suchal Riaz]

Which if the following is the strongest reducing agent?
A Cl-
B Ar
C K+
D Ca 2+
E Al3+
Can someone please answer!! Suchal Riaz GCE As and a level

strongest reducing agent will oxidise most quickly. in all of these ions on Cl- will ask as a reducing agent because:
2Cl(-1) --->CL2 +2e(-)
loss of electron is oxidasation
metal cations will gain electrons so they will reduce
as only Cl will be oxidised it will reduce other so it is strongest among these present options

 

[A star]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_s10_qp_52.pdf
q1 c diagram needed

place a plastic cup stuck on a beaker and place it on a lighted bunsen burner using a tripod stand
thermometers bulb should be half immersed in the solution. temrature range if asked should cover from 30-110 minimum

 

[saadgujjar]

place a plastic cup stuck on a beaker and place it on a lighted bunsen burner using a tripod stand
thermometers bulb should be half immersed in the solution. temrature range if asked should cover from 30-110 minimum

if u don't mind plz draw diagram