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ZeroZero82:

--- Quote from: emi on May 29, 2009, 01:34:34 pm ---can some one post about contact process and how sulphuric acid is made ?

and in moles stuff can some one post the formula;s required , and if you have any tips or easy way to work out the answers ? and solve

1- M/j 2005 paper 3 Q5 d)
2- O/N 2005 Q6  ( all parts )


thanks ALOT, you guys are Awesome  specially shogun and lilWayne  ( just dnt ovr react if ppl had diff. opinion about your fav rapper ;) )

thanks again

--- End quote ---

Obtain O2 or N2 from air by cooling the air under pressure lo liquify it. Then fractional distillation of liquid air.
Burn S in pure O2  ( S + O2 ---> SO2)
convert SO2 to 2SO3 (2SO2 + O2 <---> 2SO3 conditions:-temp. 450C, catalyst:V2O5,pressure:2atm)
Convert SO3 to Oleum(H2S2O7) (SO3 + H2SO4 --->H2S2O7)
then H2S2O7 + H2O ---> 2H2SO4 (concentrated)
;D

Shogun:
oh alrighty then, then im gonna start with the contact process first..

1)first,sulphur is allowed to react with oxygen to form sulphur dioxied(its an oxidation reaction as oxygen is taken)
2)then this sulphur dioxide is allowed to react with oxugen again to make sulphur trioxide (SO3). this reaction has some rquirements which are : catalyst: vanadium pentoxide or vanadium (v) oxide(V2O5),temperature : 450oC, and its at atmospheric preassure (but is unspecified on what ammount of atmospheric preassure).
3) sulphuric acid can esily made by just reacting water with sulphur trioxide directly, however this reaction is vilent and produces thick mist like smoke tht can cause u to choke, so to avoid this problem, the sulphur trioxide is dissolved in some sulphuric acid (labratory prepared one) to give oleum (H2S2O7)
4) then correct amount of water is added to this oleum to produce sulphuric acid of the required concentration.

and thts all with the contact process, hope this helped, then ill try to answer the moles stuff later, but the required formulas needed for moles are here:
to find the number of mole with mass and Mr and Ar.
Moles=mass/Ar or Mr

to find number moles with volume
moles= volume in dm3 / 24

if the volume was in cm3 then devide it by 10000. (to do any calculations with volume in it, the volume must be in dm3)
volume in dm3= volume in cm3/1000

to find number of moles interms of volume in dm3 and concentration (unit=(v/dm3))
moles= volume in dm3 x concentration

 :D ;D

Shogun:
hmm thier aint no section d in question 5 of paper 3 may/june,
did u mean q4'd'

aquarian93:

--- Quote from: Shogun on May 29, 2009, 12:55:48 pm ---
--- Quote from: aquarian93 on May 29, 2009, 12:50:21 pm ---
--- Quote from: aquarian93 on May 29, 2009, 12:19:21 pm ---hey u guys
wat do we need to noe abt "soaps" in organic chem. i dont understand that part
thannkss

--- End quote ---

can sum1 pls clear my doubt on this?

--- End quote ---

all u need to know about soap is how to make one. which is by reacting fat (oil) with an alkali (like sodium hydoroxide) , the chemical name for soap is sodium sterate.

and about kerosene (the correct spelling,lol) is used as fuel for jet plane with it comes paraffin where both are in the 4rth fraction.

--- End quote ---

okay. thanks =)

and how abt "what does the alkaline hydrolysis of vegetable oil produce"

unknown 101:

--- Quote from: emi on May 29, 2009, 01:34:34 pm ---can some one post about contact process and how sulphuric acid is made ?

and in moles stuff can some one post the formula;s required , and if you have any tips or easy way to work out the answers ? and solve

1- M/j 2005 paper 3 Q5 d)
2- O/N 2005 Q6  ( all parts )


thanks ALOT, you guys are Awesome  specially shogun and lilWayne  ( just dnt ovr react if ppl had diff. opinion about your fav rapper ;) )

thanks again

--- End quote ---

nov05
Q6)
a)i)number of moles of NiCO3 reacted = 0.08 mol (1:1 ratio with the sulphuric acid)
Mass of nickel carbonate reacted = mass=moles x mr --- 0.08 x 119 = 9.52 g
mass of unreacted nickel carbonate =  12.0 - 9,52 = 2.48

ii)maximum number of moles = 281 x 0.08 = 22.48
percentage yeild = 10.4/22.28  x 100 = 46.3%

b)i) by titration ( acid + alkali) and explain the process

b)ii) heat calcium and flourine together
or use precpitation method
eg. calcium nitrate + pottasium flouride ----> patasium nitrate + calcium flouride

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