« previous next »
Pages: 1 ... 195 196 [197] 198 199 ... 227   Go Down

Author Topic: CHEM AND BIO HELP AND TIPS HERE  (Read 330315 times)

Offline Raywin

  • SF Geek
  • ****
  • Posts: 393
  • Reputation: 409
  • Gender: Male
Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2940 on: June 06, 2010, 05:41:37 pm »
Quote from: Dana on June 06, 2010, 05:40:05 pm
thanks xD
so we need to know the exact conditions for only haber, contact and..cracking?

Cracking if u want, ull still get the marks, :) But the conditions for habers and contacts, YES. :D
Logged
;D

Offline MasterMath

  • SF Citizen
  • ***
  • Posts: 233
  • Reputation: 329
Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2941 on: June 06, 2010, 05:42:11 pm »
Quote from: Dana on June 06, 2010, 05:40:05 pm
thanks xD
so we need to know the exact conditions for only haber, contact and..cracking?
what rayoon said :D
Logged

Offline igext

  • SF Phantom
  • SF Citizen
  • ***
  • Posts: 267
  • Reputation: 803
  • Gender: Male
Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2942 on: June 06, 2010, 05:44:13 pm »
Quote from: MasterMath on June 06, 2010, 05:42:11 pm
what rayoon said :D
Dude you're confusin me what do we need to know other than contact and haber process?
Logged

Offline Hesham Mhd

  • Newbie
  • *
  • Posts: 37
  • Reputation: 49
Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2943 on: June 06, 2010, 05:45:07 pm »
i need help in section 6.2 of the syllabus! anyone? bcuz i get nothing from it ??? !
Logged

Offline rhea

  • SF Immigrant
  • **
  • Posts: 66
  • Reputation: 82
Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2944 on: June 06, 2010, 05:47:16 pm »
what tyoe of diagram do you draw when they ask for structural formula..
and wwhen is the other (one with branches and stuff) drawn?
Logged

Offline Raywin

  • SF Geek
  • ****
  • Posts: 393
  • Reputation: 409
  • Gender: Male
Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2945 on: June 06, 2010, 05:48:35 pm »
Quote from: rhea on June 06, 2010, 05:47:16 pm
what tyoe of diagram do you draw when they ask for structural formula..
and wwhen is the other (one with branches and stuff) drawn?

You can draw either, like the CH3-CH2 thingi or the other full stucture showing all the bond one as well, its all up to you. :) I draw both just in case.. ;)
Logged
;D

Offline rhea

  • SF Immigrant
  • **
  • Posts: 66
  • Reputation: 82
Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2946 on: June 06, 2010, 05:55:52 pm »
also there are questions on "observe"

now we dont know colours of ALL compounds..

any tips to tackle this?

also is Nitrogen oxide and sulphur dioxide- colour?

and...

how does a nitrate decompose?
Logged

Offline Raywin

  • SF Geek
  • ****
  • Posts: 393
  • Reputation: 409
  • Gender: Male
Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2947 on: June 06, 2010, 06:00:42 pm »
Quote from: rhea on June 06, 2010, 05:55:52 pm
also there are questions on "observe"

now we dont know colours of ALL compounds..

any tips to tackle this?

also is Nitrogen oxide and sulphur dioxide- colour?

and...

how does a nitrate decompose?

Umm, im guessing they will only give the Qs according to the syllabus.. they wont ask you anything out of the syllabus.

And, well, Most of the Nitrates decompose like this: 2Zn(No3)2 ---> 2ZnO + 4No2 + O2

BUT, Na and K decompose differently:
2KNo3 ---> 2KNo2 +O2  
Na decomposes in a similar way..
:) Hope tht clears ur doubt.. :D
« Last Edit: June 06, 2010, 06:03:06 pm by Raywin »
Logged
;D

Offline WARRIOR

  • SF Master
  • ******
  • Posts: 1473
  • Reputation: 51196
  • Egyptian And so damn proud . I love you jesus!
Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2948 on: June 06, 2010, 06:02:43 pm »
Quote from: rhea on June 06, 2010, 05:55:52 pm
also there are questions on "observe"

now we dont know colours of ALL compounds..

any tips to tackle this?

also is Nitrogen oxide and sulphur dioxide- colour?

and...

how does a nitrate decompose?
well , for compound su jst have to learn by heart

Nitrogen DIOXIDE is brown fumes

im not sure about sulfure dioxide  but whn u burn sulfur in air it produces blue flame


group 1 nitrates  ( EXCPT LITHIUM ) form EX: NANO3 --> NANO2 + 02 ( A NITRITE AND OXGYEN ) <---THIS IS NOT BALANCED

GROUP 2 + LI + TRANS METALS FORM  EX l ZnNo3 ---> ZnO + nitrogen dixode + oxygen <---this is nto balancd
Logged
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 Dana

  • SF Immigrant
  • **
  • Posts: 87
  • Reputation: 122
Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2949 on: June 06, 2010, 06:03:54 pm »
Quote from: MasterMath on June 06, 2010, 05:42:11 pm
what rayoon said :D
shukkraaaan (thank you :P)
Logged

Offline rhea

  • SF Immigrant
  • **
  • Posts: 66
  • Reputation: 82
Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2950 on: June 06, 2010, 06:05:20 pm »
Quote from: Kimo Jesus on June 06, 2010, 06:02:43 pm
well , for compound su jst have to learn by heart

Nitrogen DIOXIDE is brown fumes

im not sure about sulfure dioxide  but whn u burn sulfur in air it produces blue flame


group 1 nitrates  ( EXCPT LITHIUM ) form EX: NANO3 --> NANO2 + 02 ( A NITRITE AND OXGYEN ) <---THIS IS NOT BALANCED

GROUP 2 + LI + TRANS METALS FORM  EX l ZnNo3 ---> ZnO + nitrogen dixode + oxygen <---this is nto balancd


ohh..
last doubt!
s07 - q 7 b (i)
Logged

Offline CatAly$t

  • SF Citizen
  • ***
  • Posts: 241
  • Reputation: 256
  • Gender: Male
  • Ade MeLayU ke Kat $!n!???
Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2951 on: June 06, 2010, 06:06:06 pm »
how to draw this??
Logged
InshaAllah 8 A* in IGCSE....Ameen.....

Ade MeLayU ke Kat $!n!???

Offline WARRIOR

  • SF Master
  • ******
  • Posts: 1473
  • Reputation: 51196
  • Egyptian And so damn proud . I love you jesus!
Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2952 on: June 06, 2010, 06:10:24 pm »
Quote from: rhea on June 06, 2010, 06:05:20 pm

ohh..
last doubt!
s07 - q 7 b (i)

DIOL DICARBOXYIL ACID 

i cnt draw it sorry :/


Logged
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 rhea

  • SF Immigrant
  • **
  • Posts: 66
  • Reputation: 82
Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2953 on: June 06, 2010, 06:17:26 pm »
Logged

Offline igext

  • SF Phantom
  • SF Citizen
  • ***
  • Posts: 267
  • Reputation: 803
  • Gender: Male
Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2954 on: June 06, 2010, 06:17:54 pm »
Quote from: Kimo Jesus on June 06, 2010, 06:10:24 pm
DIOL DICARBOXYIL ACID 

i cnt draw it sorry :/



what conditions of rxns do we need to know other than haber and contact?
Logged
Pages: 1 ... 195 196 [197] 198 199 ... 227   Go Up
« previous next »