Author Topic: CHEM AND BIO HELP AND TIPS HERE  (Read 351119 times)

Offline MasterMath

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2760 on: June 06, 2010, 10:43:15 am »
thx. if u remember more can u pls write again ?
sure!

Offline farahkuwait

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2761 on: June 06, 2010, 10:51:08 am »
look , right now the forward reaciton is exothermic , so imagine u are heating so u are producing more of teh S03

so wherever equilibrium is , the side , reactants or products INCREASE ! , right now it is hight temp and so u go to exothermic direction and so equilbrium is at the RIGHT

but now if u decrese the temp  that means you are cooling that means u are movin in the endothermic direction to cool

so from left to right
get it?

Yeah i get it! thanks you very much! :)



Offline luv3life

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2762 on: June 06, 2010, 10:52:56 am »
@ aangel42:

Checkout the question paper from past papers. The answer sheet - it's this single paper numbered from 1-40. Next to each number, there are 4 tiny rectangles, lebelled A B C and D. For example, answer to question 1, is A. You colour inside the rectangle next to 1, labelled A.
You have to use HB pencil. Doesn't matter mechanical pencil or not. Main thing - it's an HB pencil. Best to carry 2-3 pencils. Carry an eraser too. :) Don't worry. All instructions are on the paper. It'll be fine. No worries. :)
:) LiVe LiFe As If EaCh DaY mAy Be YoUr LaSt :)

Offline Deniz

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2763 on: June 06, 2010, 10:58:09 am »
ppl im not able to download the answer paper of chemistry paper3 june 2004. can some1 download and attach it 4 me?

elemis

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2764 on: June 06, 2010, 10:59:44 am »
HERE !

Offline Deniz

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2765 on: June 06, 2010, 11:01:12 am »

elemis

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2766 on: June 06, 2010, 11:03:52 am »

Offline WARRIOR

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2767 on: June 06, 2010, 11:04:42 am »
NO secrets to SUCCESS , it is the result of 1.HARD WORK 2.GOOD PREPARATION 3.LEARNING FROM FAILURE
But it ain't how hard you hit; it's about how hard you can get hit, and keep moving forward-Balboa

**RoRo**

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2768 on: June 06, 2010, 11:14:04 am »
Fractional distillation of liquid air - HELP PLEASE!

Can someone post a link about it or so?

elemis

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2769 on: June 06, 2010, 11:14:49 am »
ur done studying and past papers ?

Just going through my TextBook now.

Offline MasterMath

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2770 on: June 06, 2010, 11:17:04 am »
thx !!
And also Adding H2 to Alkenes .. Ni 200C
And Subs. with alkanes - UV light
And the reaction between Alcohol + Acid -->Ester + water .. condition hot C.Sulphuric acid
and Adding Steam to Alkenes Either Sulphuric acid 80C / Phosporic acid 300C and 70 atm
if i remember more ill tell you

Offline Helium

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2771 on: June 06, 2010, 11:49:17 am »
Anyone Drew this??

can't get the first, want to make sure of the second
Aiming for the top

Offline Helium

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2772 on: June 06, 2010, 11:52:04 am »
1 more Plzz, Whats with 09 and drawing :P
Aiming for the top

Offline CatAly$t

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2773 on: June 06, 2010, 11:53:03 am »
how do we know which reagent is in excess??

and how do u solve the fourth question??
InshaAllah 8 A* in IGCSE....Ameen.....

Ade MeLayU ke Kat $!n!???

Offline Ivo

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2774 on: June 06, 2010, 11:56:34 am »
how do we know which reagent is in excess??

and how do u solve the fourth question??

i) 8/64=0.125

ii) 14.2/71=0.2

iii) SO2 (The one which isn't in excess is the one with the least no. of moles)

iv) 0.125 (We use moles of limiting reagent)

v) 0.125*135=16.9g
Always willing to help!  8)
"In helping others, we shall help ourselves, for whatever good we give out completes the circle and comes back to us."