Author Topic: CHEM AND BIO HELP AND TIPS HERE  (Read 333046 times)

Offline saleemsamer

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1155 on: May 17, 2010, 05:41:16 pm »

Offline Shazizzzle

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1156 on: May 17, 2010, 05:44:34 pm »
???

Join the first three points to form one straight line and extend the line throughout.
Join the last three points to form another line and extend.

Where they intersect, at about 50 deg. C, is the maximum temp. reachable.
« Last Edit: May 17, 2010, 05:49:39 pm by Shazizzzle »
•$#@2™•

Offline Ghost Of Highbury

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1157 on: May 17, 2010, 05:46:04 pm »
yes, just wat shaizzzle said..check the graph.
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Offline Ghost Of Highbury

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1158 on: May 17, 2010, 05:48:10 pm »
thats not in any textbook i have
where did you get this?

It is ritten in the textbook i have.

Roger Norris, Roger Stanbridge. Pblisher : Nelson Thornes.
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Offline da_rockstar

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1159 on: May 17, 2010, 05:53:44 pm »
hey guys could you please give me a detail about what happens in benedict test related questions for paper 3. i haven't done practiclesof bio at all and have to give exam tommorow..lol

Offline guMnam

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1160 on: May 17, 2010, 06:19:27 pm »
winter 09 p6 doubt in q4 (e) (ii)&(iii) i noe the ans i cheked the ms but i didnt understand how??????

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Offline Fastal

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1161 on: May 17, 2010, 06:26:16 pm »
It is ritten in the textbook i have.

Roger Norris, Roger Stanbridge. Pblisher : Nelson Thornes.

whats the title? is it an old book?

Offline guMnam

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1162 on: May 17, 2010, 06:26:51 pm »
winter 09 p6 doubt in q4 (e) (ii)&(iii) i noe the ans i cheked the ms but i didnt understand how??????
and also q 5 d ii

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Offline Ghost Of Highbury

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1163 on: May 17, 2010, 06:35:06 pm »
winter 09 p6 doubt in q4 (e) (ii)&(iii) i noe the ans i cheked the ms but i didnt understand how??????

cud u plz upload the paper?
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Offline Ghost Of Highbury

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1164 on: May 17, 2010, 06:35:25 pm »
whats the title? is it an old book?

CHemistry for IGCSE. no its not old.
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Offline Deniz

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1165 on: May 17, 2010, 06:36:47 pm »
what is the aim of using dry cotton wool and wet cotton wool ?

Offline WARRIOR

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1166 on: May 17, 2010, 06:37:54 pm »
if i use mg powder insted of mg ribbon with same vol and conc of acid

the rate will increase but will the total temperture rise at the end of reaction incrase?
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Offline Fastal

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1167 on: May 17, 2010, 06:41:28 pm »
CHemistry for IGCSE. no its not old.

can you post the page with the detailed tests please(scanned)? it would really help :) :)

Offline WARRIOR

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1168 on: May 17, 2010, 06:42:27 pm »
(2)

mg powder has larger s.a to react than magnesium ribbon!

large s.a = more reactant particles in contact..therefore more collisions ..therefore faster rate..faster temp chnages

when you double the volume ..the heat has to spread over a larger volume..therefore the temp chang is less
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

Offline WARRIOR

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #1169 on: May 17, 2010, 06:46:32 pm »
d is easy..L IS NAOH

what is teh cu test? NAOH  blue ppt..
and aluminute white ppt..whic dissolves in excess givng colourless solution
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