Biology; Chemistry; Physics: Post your doubts here!

[Khadija_1234]

http://papers.xtremepapers.com/CIE/...l O Level/Chemistry (5070)/5070_s11_qp_11.pdf
question no.12 .. please.

Is it B?

 

[Amnaa]

Is it B?

yes

 

[pinkywinkypuffy]

do you have notes related to these topics..??

wht topic exactly are u tslking about ?

 

[Khadija_1234]

yes

It's B because we always divide the percentage composition of an element in a compound with it's Ar to find the empirical formula

 

[Amnaa]

oxygen, hydrogen wale notes ?

 

[pinkywinkypuffy]

oxygen, hydrogen wale notes ?

hmmmmm....... i dnt rele have thm...wait i'll compile gv me an hour ...

 

[Amnaa]

hmmmmm....... i dnt rele have thm...wait i'll compile gv me an hour ...

sure

 

[Amnaa]

http://papers.xtremepapers.com/CIE/...l O Level/Chemistry (5070)/5070_s12_qp_11.pdf
question no.25

 

[asma tareen]

C as calciumoxide is basic while SiO2 is acidic i guess

 

[usama321]

C as calciumoxide is basic while SiO2 is acidic i guess

yup, SiO2 is acidic oxide.

basic oxides: group 1, group 2 (except Be)
amphoteric oxides: Be, Al, Ga, In, Ge, Sn, Pb, As, Sb, Bi
acidic oxides :B, C, Si, N, P, O, S, Se, Te

 

[asma tareen]

yup, SiO2 is acidic oxide.

basic oxides: group 1, group 2 (except Be)
amphoteric oxides: Be, Al, Ga, In, Ge, Sn, Pb, As, Sb, Bi
acidic oxides :B, C, Si, N, P, O, S, Se, Te

book me tosirf teen hain

 

[usama321]

book me tosirf teen hain

there is a very helpful thing called google

 

[asma tareen]

there is a very helpful thing called google

are all ov em in our course??

 

[pinkywinkypuffy]

http://studyguide.pk/Notes/Chemistry/O-Level-Chemistry-Notes.pdf pages 49 to 55........the atmosphere and environment .......a very important topic.. i dnt hv my own notes for this topic ..but these are useful too

 

[sourov97]

i hope it will b helpful to u guyz..if anything is missing or u want notes for other topic ..im alwayz there to help ....hope u like it.....

thanks...these are better . may i ask, where did u get it?

 

[pinkywinkypuffy]

i hope it will b helpful to u guyz..if anything is missing or u want notes for other topic ..im alwayz there to help ....hope u like it.....

let me know if these notes are good enough

 

[pinkywinkypuffy]

thanks...these are better . may i ask, where did u get it?

i complied it ...from different websites.........

 

[sourov97]

Chemitry june 06 p2 - Q A1 (c) pls explain.

 

[asma tareen]

nitrogen cux nitrogen is a non metal and non metal acidic oxide

 

[sourov97]

nitrogen cux nitrogen is a non metal and non metal acidic oxide

but this is not the correct answer, mark scheme says Al2O3