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Chemistry doubt

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red_911:

--- Quote from: ~VIN1094~ on May 24, 2010, 11:10:54 am ---Ok remember when concentrated NaCl is electrolyzed:
First the solution contains Na+ Cl- and H+ and OH- (from water). The positive inos go to the cathode, and negative ions to the anode.

At the CATHODE
the H+ ions accept electrons, since it is less reactive than Na (always elements which is more reactive 'likes' to stay in the ionic form)
2H+  +  2e-  ---> H2

At the ANODE
the Cl- ions give up the electrons more readily than the OH- ions do.
2Cl-  -->  Cl2  +  2e-

what left in the solution is Na+ and OH- which combine to form NaOH

in your ques ..is 'D' .. the indicator solution turns blue at -ve as NaOH is produced .. Chlorine doesnt  show any change in presence of an indicator solution ;)

jus understand the concept ..



--- End quote ---
lol...Thanks alot ... but y does the indicator solution turns blue only at -ve electrodde and not the whole solution ?

Vin:

--- Quote from: red_911 on May 24, 2010, 11:49:36 am ---lol...Thanks alot ... but y does the indicator solution turns blue only at -ve electrodde and not the whole solution ?

--- End quote ---

good ques .. see in this question u hav to act smart .. i think i forgot to mention .. look at the options .. u now kno tht NaOH is produced so the indicator turns blue ..there are two options with 'bule/purple' A and B .. now see A .. at -ve 'red' is given which is not possible because no acid it produced during the reaction so u r left with D .. ;)

nerdvictim:
hey, between which elements can you find carbon in the reactivity series ?!  ???

Vin:

--- Quote from: nerdvictim on May 24, 2010, 03:21:36 pm ---hey, between which elements can you find carbon in the reactivity series ?!  ???


--- End quote ---

LEARN it ! ;)

nerdvictim:

--- Quote from: ~VIN1094~ on May 24, 2010, 03:23:38 pm ---LEARN it ! ;)

--- End quote ---

:P i sure will! thank you  ;D

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