Chemistry P31

[raysonzaffar]

did u look at sacrificial protection? this is kinda like that....the cathode iron is being sacrificed to protect the iron at anode even though it is in the bubbles, they are there just to confuse the student....how many marks was that question? just in case I am wrong lol....

BOTH OF THEM WERE """""""""""""""IRON ELECTRODES""""""""""""""

 

[Osmix1995]

In physics I think I will get like

35/40 in paper 1
63/80 in paper 3
34/40 in paper 6

do u ppl think I will get an A* ? I really hope the grade boundaries are low so that I get A*

yes NSHALLAH bro

you would get 165/200 which is A* look in previous pages i told you how to calculate your marks

in the GT of 2011 o/n (which was high) yo got A*

A* was 142

 

[Razo513]

Guyzz i wrote it FeO2.H2O because i got the mole ratio 1:2:1 - what do u think?

i got the same too i think it's wrong

 

[Saadiya Ahmed]

silver has variable oxidation state so both are correct
http://en.wikipedia.org/wiki/Silver

its AgCl because the oxidation state of siver was mentioned - Ag(I)

 

[Osmix1995]

i got the same too i think it's wrong

yup supposed to be 2:3:2

 

[white rose]

i got mole ratio as 1:1.5:1....i dunno if it is correct...

 

[Saadiya Ahmed]

i got mole ratio as 1:1.5:1....i dunno if it is correct...

u were supposed to multiply the values by 2...so the final values for mole ratio were 2:3:2

 

[salvatore]

i got mole ratio as 1:1.5:1....i dunno if it is correct...

Yeah thats correct.. but u gtta convert it to 2(1:1.5:1) = 2:3:2

 

[L-Girl]

u were supposed to multiply the values by 2...so the final values for mole ratio were 2:3:2

i got it wrong

 

[white rose]

at de end i rote da formula as F2O5H4.....& i dont think dat it is rite

 

[L-Girl]

the formula and the ratio both were for 1 mark?

 

[white rose]

wht ws da ratio of Li ion : N ion??...i rote 3:1

 

[EpicLol]

BOTH OF THEM WERE """""""""""""""IRON ELECTRODES""""""""""""""

I agree....it would have been A
But since for some reason the electron flow was from B to A, B is being corroded....

 

[Saadiya Ahmed]

at de end i rote da formula as F2O5H4.....& i dont think dat it is rite

its supposed to be Fe2O3.2H2O....but i wrote Fe2O3(OH)2!!

 

[Osmix1995]

wht ws da ratio of Li ion : N ion??...i rote 3:1

yes correct if i remember well it was smth like that

 

[raysonzaffar]

I agree....it would have been A
But since for some reason the electron flow was from B to A, B is being corroded....

wat........o2 bubbles at A and still u think tht B corodes !!!!!!!!!!!!!!!!!!!!!!!!

 

[Osmix1995]

it was lithium nitride Li3N

 

[L-Girl]

wht ws da ratio of Li ion : N ion??...i rote 3:1

correct

 

[Saadiya Ahmed]

wht ws da ratio of Li ion : N ion??...i rote 3:1

me too...and obv its right
i checked by drawing the bonds between them!

 

[raysonzaffar]

wht ws da ratio of Li ion : N ion??...i rote 3:1

me too and the reason i wrote wz tht
nitride needs 3 electron more to reach the noble gas config. whereas lithium needs to lose one .......... so 3 lithium ions donate their electron to 1 nitride ion to make each stable...................
and wat wz the formula of a nitride ion .........N3- ....................ryt !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!