Author Topic: CHEM AND BIO HELP AND TIPS HERE  (Read 363313 times)

Offline The Golden Girl =D

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #600 on: May 09, 2010, 03:05:51 pm »
can u plz tell me what compounds/things that r insoluble  +++  and  what r the things that are flammable?


thx in advance  
« Last Edit: May 09, 2010, 03:12:46 pm by the golden girl »
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Offline Ghost Of Highbury

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #601 on: May 09, 2010, 03:19:48 pm »
Insoluble compounds.

Chlorides, bromides, iodides of silver and lead.

Sulfates of Calcium, barium and lead.

All hydroxides except those of group 1

All carbonates except those of group 1

Metal oxides except group 1 and 2s.

--

Flammable : Most alkanes, kersoene, petrol and naturally occurring oils.
divine intervention!

Offline haris94

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #602 on: May 09, 2010, 03:30:26 pm »
Thanks a lot adi
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Offline Ghost Of Highbury

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #603 on: May 09, 2010, 03:37:50 pm »
NO PROBLEM.
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Offline LLawliet81

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #604 on: May 09, 2010, 04:33:16 pm »
Hello all, i'm newbie here...
I take A-Level for Biology on this May-June session and still need some helps.

May i ask my doubt about how to answer the question, whether the answers are short and simple like in the mark scheme or we must explain more on every point in mark scheme ? And what is the meaning of word "reference" in mark scheme?

Bonus Question: How to answer the last part (looong essay part) of P4 ?

Need your help, because my school teacher never give us explanation about it.
Thx before and sorry if my questions are out of the thread :)

Offline Fastal

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #605 on: May 09, 2010, 05:01:09 pm »
Hello all, i'm newbie here...
I take A-Level for Biology on this May-June session and still need some helps.

May i ask my doubt about how to answer the question, whether the answers are short and simple like in the mark scheme or we must explain more on every point in mark scheme ? And what is the meaning of word "reference" in mark scheme?

Bonus Question: How to answer the last part (looong essay part) of P4 ?

Need your help, because my school teacher never give us explanation about it.
Thx before and sorry if my questions are out of the thread :)
this is the igcse forum
i think you should go here-https://studentforums.biz/index.php/board,82.0.html

holtadit

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #606 on: May 09, 2010, 05:54:46 pm »
this is the igcse forum
i think you should go here-https://studentforums.biz/index.php/board,82.0.html

Thanks +rep.

Offline The Golden Girl =D

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #607 on: May 09, 2010, 07:08:39 pm »
Insoluble compounds.

Chlorides, bromides, iodides of silver and lead.

Sulfates of Calcium, barium and lead.

All hydroxides except those of group 1

All carbonates except those of group 1

Metal oxides except group 1 and 2s.

--

Flammable : Most alkanes, kersoene, petrol and naturally occurring oils.

thx  :D
Verily, in the remembrance of Allah do hearts find rest(13:28)

Please, Don't forget to Include GG in your Prayers =D

Offline Baladya

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #608 on: May 09, 2010, 08:04:22 pm »
Insoluble compounds.

Chlorides, bromides, iodides of silver and lead.

Sulfates of Calcium, barium and lead.

All hydroxides except those of group 1

All carbonates except those of group 1

Metal oxides except group 1 and 2s.

--

Flammable : Most alkanes, kersoene, petrol and naturally occurring oils.

OMG I freakin h8 this and the Cations/Anions Test man  >:( Can't manage to memorize them  :(  :P
Looks like i ran out of cool signatures :|

Offline $H00t!N& $t@r

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #609 on: May 09, 2010, 09:16:08 pm »
I need help with moles!
 http://www.freeexampapers.us/IGCSE/Chemistry/CIE/2005%20Jun/0620_s05_qp_3.pdf

Q4d! I got the moles for CaSO4 and H20 (0.58 mol and 1.16 mol, respectively) but I'm confused with the x. Do you add the moles for CaSO4 and H20 to get x ???

Secondly, http://www.freeexampapers.us/IGCSE/Chemistry/CIE/2003%20Nov/0620_w03_qp_3.pdf
Q5d! (moles again) My question is how do you know that that 0.125 mol of SO2Cl2 was formed?  :-\
 
"If A equals success, then the formula is:
A=X+Y+Z, X is work. Y is play. Z is keep your mouth shut"- Albert Einstein

holtadit

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #610 on: May 10, 2010, 04:16:20 am »
Quote
Q4d! I got the moles for CaSO4 and H20 (0.58 mol and 1.16 mol, respectively) but I'm confused with the x. Do you add the moles for CaSO4 and H20 to get x

Do it step by step - dont jump.

First find the no. of moles of CaSO4

79.1/136  = 0.582 moles

20.9/18    =  1.16 moles

Notice we are in effect finding the empirical formula hence:

0.582/0.582 = 1                and                      1.16/0.582 = 2

Thus X = 2

Offline SEL123

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #611 on: May 10, 2010, 05:44:07 am »
Can this page ALSO help me with Bio??
If it can
Can someone please help me:
My school gave us waaaaaaaaaaay too much information..
And I just want to be sure:
When making cheese,bread, wine,yoghurt, and beer, what do we have to know EXACTLY
Our school gave us steps and all those stuff
Should we ONLY know what the study guide tells us on this part (the results, and a brief explanation)???
To repeat what others have said, requires education, to challenge it, requires brains.

Offline $H00t!N& $t@r

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #612 on: May 10, 2010, 06:23:22 am »
Do it step by step - dont jump.

First find the no. of moles of CaSO4

79.1/136  = 0.582 moles

20.9/18    =  1.16 moles

Notice we are in effect finding the empirical formula hence:

0.582/0.582 = 1                and                      1.16/0.582 = 2

Thus X = 2

Oh, I get it now thanks Ari!  :)
"If A equals success, then the formula is:
A=X+Y+Z, X is work. Y is play. Z is keep your mouth shut"- Albert Einstein

holtadit

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #613 on: May 10, 2010, 06:39:36 am »
Can this page ALSO help me with Bio??
If it can
Can someone please help me:
My school gave us waaaaaaaaaaay too much information..
And I just want to be sure:
When making cheese,bread, wine,yoghurt, and beer, what do we have to know EXACTLY
Our school gave us steps and all those stuff
Should we ONLY know what the study guide tells us on this part (the results, and a brief explanation)???

I'll ask nid to help you.

Oh, I get it now thanks Ari!  :)

No problemo ;)

Offline The Golden Girl =D

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #614 on: May 10, 2010, 07:24:20 am »
OMG I freakin h8 this and the Cations/Anions Test man  >:( Can't manage to memorize them  :(  :P


chill ..... u must understand it first so that when u memorize it'll be easy for u to memorize ,k ?
Verily, in the remembrance of Allah do hearts find rest(13:28)

Please, Don't forget to Include GG in your Prayers =D