SL Topic 9 : Redox processes
Foreachquestionchoosetheansweryouconsidertobethebest.
1.Whichiscorrectstatementaboutreduction?
A.Itinvolvesthelossofhydrogen.
B.Itinvolvestheadditionofoxygen.
C.Itinvolvestheadditionofelectrons.
D.Itinvolvesanincreaseinoxidationnumber.
2.Inwhichspeciesdoesmanganesehaveanoxidationstateof+3?
A.MnSO4
B.KMnO4
C.Mn2O3
D.MnO2
3.WhatisthecorrectnameforFeSO4?
A.iron(II)sulfite
B.iron(III)sulfite
C.iron(II)sulfate
D.iron(II)sulfide
Dr Geoffrey Neuss, InThinking
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http://www.thinkib.net/chemistry
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4.WhatchangeoccurstovanadiumduringtheconversionofVO3–(aq)toVO2+?
A.Itundergoesreductionanditsoxidationstatechangesfrom+5to+4.
B.Itundergoesreductionanditsoxidationstatechangesfrom+3to+2
C.Itundergoesoxidationanditsoxidationstatechangesfrom–1to+2
D.Itundergoesoxidationanditsoxidationstatechangesfrom+6to+2
5.Whataretheoxidationstatesoftheelementsinsulfuricacid,H2SO4?
hydrogen
sulfur
oxygen
A.
+2
+6
-8
B.
+1
+6
-2
C.
+1
-2
-2
D.
+1
-2
0
6.Whicharecorrectstatements?
I.TheoxidationstateofoxygeninH2O2is–1
II.TheoxidationstateofnitrogeninN2H4is–2
III.TheoxidationstateofhydrogeninMgH2is–1
A.IandIIonly
B.IandIIIonly
C.IIandIIIonly
D.I,IIandIII
Dr Geoffrey Neuss, InThinking
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http://www.thinkib.net/chemistry
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7.Whichchangeinvolvesnitrogenbeingoxidized?
A.N2H4→NH2–
B.NO2→N2O4
C.NO3–→N2O5
D.N2O→NO
8.Whichiscorrectaboutthefollowingreaction?
2I–(aq)+Cl2(aq)→I2(aq)+2Cl–(aq)
A.I–(aq)gainselectronsandisreduced.
B.Cl2(aq)loseselectronsandisreduced.
C.I–(aq)loseselectronsandisoxidized.
D.Cl2(aq)gainselectronsandisoxidized.
9.Whichchangesareexamplesofreduction?
I.Cu2+→Cu+
II.NH3→N2
III.MnO4–→MnO2
A.IandIIonly
B.IandIIIonly
C.IIandIIIonly
D.I,IIandIII
Dr Geoffrey Neuss, InThinking
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http://www.thinkib.net/chemistry
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10.Whichisthecorrectorderofthedecreasingoxidisingabilityofthegroup17elements
(strongestoxidizingagentfirst)?
A.F2>Cl2>Br2>I2
B.Cl2>Br2>I2>F2
C.I2>Br2>Cl2>F2
D.F2>I2>Br2>Cl2
11.Whichreactionisnotaredoxreaction?
A.H2S(g)+Cl2(aq) 2HCl(aq)+S(s)
B.Zn(s)+2HCl(aq) ZnCl2(aq)+H2(g)
C.Ag+(aq)+Cl–(aq) AgCl(s)
D.3H2(g)+N2(g) 2NH3(g)
12.Inwhichreactionsarecarbonatomsoxidized?
I.C2H5OH→CH3CHO+2H++2e–
II.C2H4+Br2→C2H4Br2
III.C2H5Br+OH–→C2H5OH+Br–
A.IandIIonly
B.IandIIIonly
C.IIandIIIonly
D.I,IIandIII
Dr Geoffrey Neuss, InThinking
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http://www.thinkib.net/chemistry
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13.WhatisthecoefficientforH+(aq)whentheredoxequationbelowisbalanced?
MnO4–(aq)+Fe2+(aq)+H+(aq)→Mn2+(aq)+Fe3+(aq)+H2O(l)
A.2
B.4
C.5
D.8
14.Whichisthecorrectcombinationofstatementsforthefollowingreaction?
Cr2O72–(aq)+3H2O2(l)+8H+(aq)→2Cr3+(aq)+3O2+7H2O(l)
species
undergoes
actsas
Cr2O72-(aq)
oxidation
oxidizingagent
B.
H2O2(l)
oxidation
reducingagent
C.
H2O2(l)
reduction
oxidizingagent
D.
Cr2O72-(aq)
reduction
reducingagent
A.
15.Avoltaiccellisconstructedfromahalf-cellconsistingofapieceofironinasolutionof
iron(II)ionsconnectedtoahalf-cellconsistingofapieceofcopperinasolutionof
copper(II)ions.Ironismorereactivethancopper.Whichstatementiscorrect?
A.Ironatomsloseelectrons.
B.Electronsflowfromthecopperhalf-celltotheironhalf-cell.
C.Themassofthenegativeelectrodeincreases.
D.TheconcentrationofCu2+(aq)ionsincreases.
Dr Geoffrey Neuss, InThinking
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http://www.thinkib.net/chemistry
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16.Considerthefollowingreactionswhichalloccurinsolutionatroomtemperature.
Fe(s)+Cu2+(aq)→Fe2++Cu(s)
Mg(s)+Zn2+(aq)→Mg2++Zn(s)
Zn(s)+Fe2+(aq)→Zn2++Fe(s)
Whichisthecorrectcombinationofthestrongestoxidizingagentandthestrongest
reducingagent?
strongestoxidizingagent
strongestreducingagent
Zn(s)
Fe2+(aq)
B.
Cu2+(aq)
Mg(s)
C.
Mg(s)
Cu2+(aq)
D.
Cu(s)
Mg2+(aq)
A.
17.Whatprocessoccursatthepositiveelectrodeinavoltaiccellandinanelectrolyticcell?
voltaiccell
electrolyticcell
A.
oxidation
reduction
B.
oxidation
oxidation
C.
reduction
oxidation
D.
reduction
reduction
Dr Geoffrey Neuss, InThinking
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http://www.thinkib.net/chemistry
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18.Whichoccurduringtheelectrolysisofmoltensodiumchloride?
I.Chlorinegasformsatthepositiveelectrode
II.Electronsflowthroughthemoltenliquid
III.Reductionoccursatthenegativeelectrode
A.IandIIonly
B.IandIIIonly
C.IIandIIIonly
D.I,IIandIII
19.Whicharecorrectstatementsaboutcells?
I.Electrolyticcellscontainasaltbridge
II.Inavoltaiccellelectronsareproducedatthenegativeelectrode
III.Inanelectrolyticcellcationsacceptelectronsatthenegativeelectrode
A.IandIIonly
B.IandIIIonly
C.IIandIIIonly
D.I,IIandIII
Dr Geoffrey Neuss, InThinking
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http://www.thinkib.net/chemistry
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20.Whichstatementiscorrectabouthowcurrentisconductedinanelectrolyticcell?
A.Electronsmovethroughtheelectrolyteandtheexternalcircuit.
B.Ionsmovethroughtheelectrolyteandthroughtheexternalcircuit.
C.Ionsmovethroughthesaltbridgeandelectronsmovethroughtheexternalcircuit.
D.Ionsmovethroughtheelectrolyteandelectronsmovethroughtheexternalcircuit.
Dr Geoffrey Neuss, InThinking
©
http://www.thinkib.net/chemistry
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