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During the electrolysis of copper II sulphate between platinum electrodes, if litmus solution is added...

During the electrolysis of copper II sulphate between platinum electrodes, if litmus solution is added to the anode compartment,
  • A. the litmus turns blue but no gas is evolved
  • B. the litmus turns blue and oxygen is evolved
  • C. the litmus turns blue and hydrogen is evolved
  • D. the litmus turns red and oxygen is evolved
  • E. the litmus turns red and then becomes colourless
Correct Answer: Option D
Explanation
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Contributions (27)

Goodness kalu
6 years ago
Durin d electrolysis of copper usin platinum electrode,CU nd H migrate 2d cathode while,SO4 nd OH migrate 2d anode.CU is den dischargd preferentialy at d cathode,acquirin 2electrons nd is depositd as metallic copper,while,OH is dischargd prefrentialy at d anode n depositd as gaseous oxygen.den d SO4 nd H stil in d solution react,thereby makin d solution acidic nd den changin d litmus paper 2red whch is d tst 4acids.
Davidloove
6 years ago
admin d correct ans is b.cos oxidation take place at d anode in which OH ION is liberated nd wit further reaction O2 gas is evolve.note OH ION is a basic ion so wen test wit litmus gives blue not red.2oh- + 2oh- : 2h2o + o2.nd 2O2: O2-2 + 4E-.GBAM*
bright999
3 years ago
Some of you are on point but probably didn't understand the question...it says AT THE ANODE..here OH- is deposited and basisity increases which of course turn red litmus blue and oxygen is given off.

4OH -> 2H2O +O2........i rest My case.
Lil Ross
6 years ago
At the anode,OH ions are being depoisted..these ions turn blue litmus paper red
  • toeseen: by the hydrolysis of cuso4..cu+,h+,so42-,oh-...are the ions, the anode is the positive electrode which is atrracted to the negative ions i.e the anions, oh- is thus deposited because it is platinum electrode and higher in the ecs,and since oh- is a basic ion, alkali ion..ot turns red litmus blue...and oxidation occurs at the anode to liberate oxygen gas!
    Like 1    Dislike 0   5 years ago
drokoyei
5 years ago
100% correct @ goodness
kulrosy
4 years ago
at the anode, the hydroxyl ion is discharged and we have.... 4OH-->2H2O+O2. solution is acidic by the presence of H+ and SO4^2- ions combined into H2SO4. therefore, the litmus turns red and oxygen is evolved..
tammy
9 months ago
The correct answer is B. At the anode OH- is given off which combines with itself to give of oxygen Hence the presence of OH- ions makes red litmus applied to the anode to turn blue due to its alkalinity.
bibilove
7 years ago
the litmus turns red because at the anode is the base(anion)
  • Ijeoma henry: Acid turns blue litmus red,copper 2 sulphate is an acid and oxygen is lost at d +ve electrode xo ur xplanation z wrng
    Like 0    Dislike 0   6 years ago
  • Ben Onuike: guys, d copper sulphate is nt in aqueous form so d only anion at d anode (So4)^-2 which wil produce sulphur iv oxide and oxygen gas on discharging,an acid anhyride which wil dissolve in d solution of d litmus to turn it red
    Like 1    Dislike 0   4 years ago
  • Jay -jay. west: pt is inert! there4 SO2-4 remains in solution making the solution axidik
    Like 0    Dislike 0   4 years ago
CenSmart
2 months ago
D is the correct answer following hittorf's law
balogun toluwalope
6 years ago
CUSO4 In Anode,OH is discharge b'cos SO4 is mor electronegativ than OH .OH- _e-=OH.4OH_4e-=2H2O+02+4e-.So oxygen is evolved.
Davikky
6 years ago
Reply to abdul,u're also wrong
  • cyberformz: as d Cu ion nd OH- ion er discharged d soln bcoms acidic due to d formatn of oil of vitriol cos H ion nd So4 ion z left in d soln
    Like 0    Dislike 0   4 years ago
Mujcokid
3 years ago
Yeah correct
evans4life
4 years ago
goodness u re correct

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