Author Topic: CHEM AND BIO HELP AND TIPS HERE  (Read 357183 times)

Offline Vin

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #3015 on: June 06, 2010, 09:41:59 pm »
Hey Ya could someone pls do this question its really wierd cant figure it out at all


"the vol. of phosphate soln used in cm3 is half the height of the ppt in mm
also at 8cm3 all the soln is used up. tht is because adding more does not increase the height of the ppt meaning there was no further reaction on adding more.
also the formula is T3(PO4)2-----because

u take it as 12cm3 of T nitrate react with 8cm3 of sodium phosphate (thts wen all the reactants r used up)
so.....12:8...simplify it
12:8
6:4
3:2
and therefore u get T3(PO4)2"

courtesy : mohit123

Offline $H00t!N& $t@r

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #3016 on: June 06, 2010, 09:46:53 pm »
OK look at the graph, mass of the plate is constant after some time. What does it mean? No more Zn is reacting, right? So the reaction is finished. Therefore Zn is excess as it is still left after the reaction is over. Got it?
oh i see... Thanks  :)
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Offline The InViSiBlE GIrl (Eva)

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #3017 on: June 06, 2010, 10:07:56 pm »
ok gotcha thanks!!

"the vol. of phosphate soln used in cm3 is half the height of the ppt in mm
also at 8cm3 all the soln is used up. tht is because adding more does not increase the height of the ppt meaning there was no further reaction on adding more.
also the formula is T3(PO4)2-----because

u take it as 12cm3 of T nitrate react with 8cm3 of sodium phosphate (thts wen all the reactants r used up)
so.....12:8...simplify it
12:8
6:4
3:2
and therefore u get T3(PO4)2"

courtesy : mohit123

LiFe Is NoT tHe MeAsUrE oF tHe NuMbEr Of BrEaDtHs We TaKe, BuT rAtHeR oF tHe MoMeNtS tHaT tOoK oUr BrEaDtHs AwAy <3 LIFE :-D

Offline 7ooD

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #3018 on: June 07, 2010, 01:45:51 am »
i have urgent question in 2004 may june q 4 b iii i dnt get it at all and same paper 7 b (ii) in ms they rounded the 0.125 to 0.1  suppose it waz cuz they gave masses to 1 decimal why they didnt do the same in c (i) and (ii)
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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #3019 on: June 07, 2010, 05:16:08 am »
Attach the paper please

Offline SNA

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #3020 on: June 07, 2010, 06:45:43 am »
i don't know bout others, but i think i died in the examination room!!
ill be lucky to get a C.  :'(

Offline CatAly$t

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #3021 on: June 07, 2010, 07:46:09 am »
pls,

how to draw this??
InshaAllah 8 A* in IGCSE....Ameen.....

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Offline PeaceMaker

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #3022 on: June 07, 2010, 08:18:43 am »
Question 3a, How do you know which one is which and thanks! Good luck to you all people!

Offline Girlie45

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #3023 on: June 07, 2010, 08:26:00 am »
i don't know bout others, but i think i died in the examination room!!
ill be lucky to get a C.  :'(


Whaat ??  :o  what varient did you do ??

Offline rameeziiii

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #3024 on: June 07, 2010, 08:35:58 am »
Question 3a, How do you know which one is which and thanks! Good luck to you all people!
working

Offline luv3life

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #3025 on: June 07, 2010, 08:38:19 am »
Chem P3. It was okay. Not hard, but not easy either.

Wasn't too good for me, 'because I guess I didn't study enough. Those 9 days holz-ugh. :P
:) LiVe LiFe As If EaCh DaY mAy Be YoUr LaSt :)

Offline CatAly$t

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #3026 on: June 07, 2010, 08:40:58 am »
InshaAllah 8 A* in IGCSE....Ameen.....

Ade MeLayU ke Kat $!n!???

Offline Vin

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #3027 on: June 07, 2010, 08:47:36 am »

Offline rameeziiii

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #3028 on: June 07, 2010, 08:47:54 am »
noble gas =  D (cuz of 8 electrons in outermost shell...therefore a full shell)
soft metal =  E (cuz all group I metals are soft)
covalent =  F (cuz of being in group I and therefore form covalent bonds with group V)
giant structure =  B (group IV form macromolecular structers)
ion =  A ( group V form X3- ions

Offline CatAly$t

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #3029 on: June 07, 2010, 08:53:26 am »
Um, this should be right.

at last... ;)

thx  ;D
InshaAllah 8 A* in IGCSE....Ameen.....

Ade MeLayU ke Kat $!n!???