Chemistry P31

[bluefa1con]

which varriant did u take? b/c i dont remember such a formula.

variant 1
the title of the thread

 

[areebaization]

Salt acts as a catalyst & speeds up the rusting process!

I wrote that too r u sure abt it? :/

 

[Abu mota]

I wrote that too r u sure abt it? :/

dont want u to feel bad but it is wrong actually it is because it provides more ions,ions speed up the reaction, u cant say it acts as a catalyst because the ions are changed by the reaction, and the definition of a catalyst is a substance that speeds up a reaction without being changed by the reaction.

 

[Beedo]

I wrote that too r u sure abt it? :/

I wrote that too , I think it is or I hope so
it is a suggestion

 

[Asimxd]

you dont always believe the smartest guy
people often screw up
answer should be B bcz on A redox reaction is happening
on B electrons are lost

Amro the smartest kid isn't basil it's shahd... She said its B

 

[Naser Al-Ayyoub]

No, in a cell, the negative electrode is the anode, and oxidation occurs there

dude they staed in the question paper wugh is negative and wich is positive

 

[Naser Al-Ayyoub]

it's correct.
that's what i did.

But H2O is one mole only, you had to use the atomic mass not proton nuber for that molecule and the rest proton number.

 

[Naser Al-Ayyoub]

its ok! dnt wry... im sure u will be fine

daaaaaaaaaaamn i did the whole question wrong

 

[Naser Al-Ayyoub]

guys!!! why is calcium carbonate better than calcium oxide???

because it is soluble

 

[Naser Al-Ayyoub]

no calcium oxide is slightly insoluble ,,, so it is solouble

dude they said benefit of calcium carbonate not calcium oxide

 

[Micro961]

The reagent that converts alcohol to carboxylic acid.. I wrote potassium dichromate but i forgot to say ACIDIFIED potassium dichromate.. I will get it wrong right?

 

[Beedo]

The reagent that converts alcohol to carboxylic acid.. I wrote potassium dichromate but i forgot to say ACIDIFIED potassium dichromate.. I will get it wrong right?

I wrote acidified then deleted it by the end of the time

 

[reya]

1 thing that I don't got HOW COME 200? 40+80+60=180? 20 marks 4 what?

 

[reya]

condensation

I was confused but i got it r8.

 

[Beedo]

1 thing that I don't got HOW COME 200? 40+80+60=180? 20 marks 4 what?

you do it like this
p6 = 40 marks
p1=60 marks
p3=100 marks

 

[reya]

paper 3 is 80 as far i know !

 

[Manobilly]

Yeah ,They do it in that way ,like If u get 150 out of 160 which is total for all ,they will divide 150/160 than multiply by 200 to get mark out of 200 ,this actually imrpoves ur grade

 

[Beedo]

paper 3 is 80 as far i know !

please understand what I am saying
paper 6 is 20% only of the mark (I know it is 60 marks in the paper but it worth 40 marks out of 200 only)
paper 1 is 30% ( It is 40 in the paper but worth 60 marks out of 200)
paper 3 is 50% (it is 80 marks in the paper but worth 100 marks out of 200)
if you got for example 45/60 in paper 6 , 60/80 in paper 3 , 36/40 in paper 1 then it is calculated like this
45*40/60=30 marks
60*100/80=75 marks
36*60/40=54 marks
then the total is 30+75+54=159 out of 200
equal 80% approximately
Hope you understood this time

 

[Ahmed Abdullah]

you dont always believe the smartest guy
people often screw up
answer should be B bcz on A redox reaction is happening
on B electrons are lost

but isnt it that electron flow through the circuit and comes back again at the negative electrode

Both possibly

 

[areebaization]

Salt acts as a catalyst & speeds up the rusting process!

dont want u to feel bad but it is wrong actually it is because it provides more ions,ions speed up the reaction, u cant say it acts as a catalyst because the ions are changed by the reaction, and the definition of a catalyst is a substance that speeds up a reaction without being changed by the reaction.

salt as a catalyst is right Woot woot!
source: http://www.rustblock.com/rust-process-defined.html