Author Topic: CHEM AND BIO HELP AND TIPS HERE  (Read 330384 times)

Offline The Golden Girl =D

  • Without Allah I'm nothing <3
  • Honorary Member
  • SF Overlord
  • *****
  • Posts: 13757
  • Reputation: 65532
  • Ain't Nothin worth your tears =D
    • www.thegoldengirl157.blogspot.com
Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #555 on: May 07, 2010, 03:35:19 pm »
guys whenever a question comes and any oxide "batani7!!" ....i don't anythin hat's related to oxides ..... and stuff ...the only thing i kno abt oxides is that the non-mtealic r acidic and the metallic r basic ..and there r some amphotaric ....... can someone plz explain to me ..

ummm ohh and another thing ....there is this weird question that i'd like u to look at, it's jun 2000 paper 1 chem ig question 26) ..

http://www.freeexampapers.us/IGCSE/Chemistry/CIE/1993-2003/ChemistryExamP1.pdf

thx in advance
« Last Edit: May 07, 2010, 03:38:04 pm by the golden girl »
Verily, in the remembrance of Allah do hearts find rest(13:28)

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

Offline The Golden Girl =D

  • Without Allah I'm nothing <3
  • Honorary Member
  • SF Overlord
  • *****
  • Posts: 13757
  • Reputation: 65532
  • Ain't Nothin worth your tears =D
    • www.thegoldengirl157.blogspot.com
Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #556 on: May 07, 2010, 03:38:46 pm »
when the questions says smthn is below ph 7 , does that mean it's acidic or basic?

thx in advacne :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 Ghost Of Highbury

  • O_o_O lala!
  • SF Farseer
  • *******
  • Posts: 4096
  • Reputation: 41428
  • Gender: Male
  • Namaskaram!
Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #557 on: May 07, 2010, 03:40:46 pm »
below pH 7 - acidic. u must be clear with these basic concepts by now, acids and bases is a very common topic. :)

By the way, @hesham - heres the working wid acid electrolyte.

the hydrogen (H2) loses electrons.. 2H2 --> 4H+ + 4e- which travel through the circuit to the cathode and react with O2..also the H+ ions from the acid electrolyte meets the electrons and O2 at the cathode

the reaction

O2 + 4H+ + 4e- = 2H2O

---
The H+ ions removed from the electrolyte are replaced by those produced at the anode.
divine intervention!

nid404

  • Guest
Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #558 on: May 07, 2010, 03:49:30 pm »
thanks adi +rep 

holtadit

  • Guest
Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #559 on: May 07, 2010, 03:49:57 pm »
guys whenever a question comes and any oxide "batani7!!" ....i don't anythin hat's related to oxides ..... and stuff ...the only thing i kno abt oxides is that the non-mtealic r acidic and the metallic r basic ..and there r some amphotaric ....... can someone plz explain to me ..

ummm ohh and another thing ....there is this weird question that i'd like u to look at, it's jun 2000 paper 1 chem ig question 26) ..

http://www.freeexampapers.us/IGCSE/Chemistry/CIE/1993-2003/ChemistryExamP1.pdf

thx in advance

Okay the answer is 26 B. Heres the explanation coming up....
« Last Edit: May 07, 2010, 03:55:11 pm by Ari Ben Canaan »

Offline Ghost Of Highbury

  • O_o_O lala!
  • SF Farseer
  • *******
  • Posts: 4096
  • Reputation: 41428
  • Gender: Male
  • Namaskaram!
Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #560 on: May 07, 2010, 03:52:39 pm »
guys whenever a question comes and any oxide "batani7!!" ....i don't anythin hat's related to oxides ..... and stuff ...the only thing i kno abt oxides is that the non-mtealic r acidic and the metallic r basic ..and there r some amphotaric ....... can someone plz explain to me ..

ummm ohh and another thing ....there is this weird question that i'd like u to look at, it's jun 2000 paper 1 chem ig question 26) ..

http://www.freeexampapers.us/IGCSE/Chemistry/CIE/1993-2003/ChemistryExamP1.pdf

thx in advance

cud u be more specific abt oxides, i mean what exactly do u want to know abt?

and wat the helll is batani7? never heard abt that :-/
 
divine intervention!

holtadit

  • Guest
Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #561 on: May 07, 2010, 03:58:18 pm »
Okay the answer is 26 B. Heres the explanation coming up....

Magnesium and Zinc react with steam to form HYDROGEN !!! SO those two arent correct.

Copper is unreactive and doesnt react with steam so it can be the correct one.


Thus, Iron is the only one that when heated and reacted with Steam forms its OXIDE and HYDROGEN GAS.

Offline Ghost Of Highbury

  • O_o_O lala!
  • SF Farseer
  • *******
  • Posts: 4096
  • Reputation: 41428
  • Gender: Male
  • Namaskaram!
Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #562 on: May 07, 2010, 04:00:48 pm »
@Ari - its B, not A.

Copper will not displace Hydrogen. Iron will. and give release the hydrogen.
divine intervention!

holtadit

  • Guest
Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #563 on: May 07, 2010, 04:02:00 pm »
@Ari - its B, not A.

Copper will not displace Hydrogen. Iron will. and give release the hydrogen.


Sorry, it was a typo I meant B. I changed it and  gave an explanation. :D

Offline Ghost Of Highbury

  • O_o_O lala!
  • SF Farseer
  • *******
  • Posts: 4096
  • Reputation: 41428
  • Gender: Male
  • Namaskaram!
Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #564 on: May 07, 2010, 04:02:50 pm »
its okay. +rep

anyway, gas Q is H2, as the metal will displace hydrogen not oxygen.

out of copper and iron, iron is above hydrogen in the series, thus iron.
divine intervention!

Offline The Golden Girl =D

  • Without Allah I'm nothing <3
  • Honorary Member
  • SF Overlord
  • *****
  • Posts: 13757
  • Reputation: 65532
  • Ain't Nothin worth your tears =D
    • www.thegoldengirl157.blogspot.com
Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #565 on: May 07, 2010, 04:13:22 pm »
cud u be more specific abt oxides, i mean what exactly do u want to know abt?

and wat the helll is batani7? never heard abt that :-/
 

i'm srry abt batani7 , it's actually an arabian MSN word ...srry i though u were arabian :(....my bad  :-[

as for the oxides ....i guess i just wanna to know where is hydrogen in the reactivity series........ actually the whole reactivity series ..i want it all ....  can u give me a link that shows the reactivity series ...includin carbon and hydrogen ....cuz the one i have doesn't have hydrogen ....no idea y?!?!

as for the oxides .....i don't kno who reacts with what to give for ex hydrogen ,u see
  hope u got my point ...

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

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

holtadit

  • Guest
Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #566 on: May 07, 2010, 04:16:11 pm »


Here. Right click and select view image to enlarge


Only a metal compound higher than Hydrogen can displace it from steam and hence form METAL OXIDE and STEAM
« Last Edit: May 07, 2010, 04:17:44 pm by Ari Ben Canaan »

Offline The Golden Girl =D

  • Without Allah I'm nothing <3
  • Honorary Member
  • SF Overlord
  • *****
  • Posts: 13757
  • Reputation: 65532
  • Ain't Nothin worth your tears =D
    • www.thegoldengirl157.blogspot.com
Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #567 on: May 07, 2010, 04:18:35 pm »


Here. Right click and select view image to enlarge


Only a metal compound higher than Hydrogen can displace it from steam and hence form METAL OXIDE and STEAM

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

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

Offline Ghost Of Highbury

  • O_o_O lala!
  • SF Farseer
  • *******
  • Posts: 4096
  • Reputation: 41428
  • Gender: Male
  • Namaskaram!
Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #568 on: May 07, 2010, 04:21:22 pm »
the link, here : http://www.zephyrus.co.uk/thereactivityseries.html

and abt the reactions, im still not sure wat u want.

"who reacts to what" completely depends on the q. like here.

steam reacted with a metal i.e iron

Steam - H2O

iron - Fe

H2O + Fe --> FeO + H2.

Iron displaced Hydrogen.
divine intervention!

Offline The Golden Girl =D

  • Without Allah I'm nothing <3
  • Honorary Member
  • SF Overlord
  • *****
  • Posts: 13757
  • Reputation: 65532
  • Ain't Nothin worth your tears =D
    • www.thegoldengirl157.blogspot.com
Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #569 on: May 07, 2010, 04:29:05 pm »
the link, here : http://www.zephyrus.co.uk/thereactivityseries.html

and abt the reactions, im still not sure wat u want.

"who reacts to what" completely depends on the q. like here.

steam reacted with a metal i.e iron

Steam - H2O

iron - Fe

H2O + Fe --> FeO + H2.

Iron displaced Hydrogen.

okay i'll give u all the questions that i have doubt in that r related to oxides ,k ? ....but plz do explain cuz i kno what the answers r cuz of the ms ..,k?

well herei  go :

jun2001 question 14)
nov 2001 question 21)
nov 2003 q 16) ..19) and 26)
jun 2004 q 9)..14)..26)
nov q 11)


i kno that's alot .....well my bro is pain in the neck .hence i'll sign out right  now ...but i'll be back abd 2 hours later or smthn ..... and i really would apprectiate it if u would have answered me by then ...


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

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