2b soal soal titrasi redoks

Download 2b Soal Soal Titrasi Redoks

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Soal-soal Titrasi Redoks

Soal-soal Titrasi Redoks

sample mass=0,4185gKMnO4 titration=0,025M41,27mL%Fe2O3=?mol Fe2O3=1/2*mol Fe=1/2*5*mol KMNO4=5/2*(V*M)KMnO42,5794mmolmassa Fe2O3=412,7mg98,61%

48sample=0.4185g=418.5mgTitration Fe2+KMnO4Vol=41.27mLM=0.025MMol KMnO4= (M*V)=1.03175mmolReaction: 5 Fe2+ + KMnO4 === 5 Fe3+ + Mn2+mol Fe2+ = 5* mol KMnO4=5.15875mmolReaction: 2 Fe2+ === 2 Fe3+ ===== Fe2O3mol Fe2O3 = 0,5*mol Fe2+ =2.579375mmolmass Fe2O3= mol*Mr Fe2O3=412.7mg%Fe2O3= mass Fe2O3/mass sample*100%=98.61%

50Walden reductor: UO22+ --> U4+Addition of Fe3+: U4++ 2Fe3+ ---> U6+ + 2Fe2+ Titration: 6 Fe2+ + K2Cr2O7 --> 6 Fe3+ + 2 Cr3+sample=0.315g=315mgTitration:Vol=10.52mLM=0.00987Mmmol K2Cr2O7= (V*M)=0.1038324mmolmmol Fe2+ =6 * mmol K2Cr2O7=0.6229944mmolmmol U4+ =0,5 * mmol Fe2+ =0.3114972mmolmass U= mmol U4+ * Ar (U)=74.1453389841mg%U= mass U/mass sample *100=23.54%

Ar U=238.02891

51Cr=51.9961Fe55.845Area=30cm2density Cr=7.2g/cm3oxidizing: 2Cr3+ === Cr2O72-Addition of Fe(NH4)2(SO4)26H2O=500.0mgReactionCr2O72- + 6Fe2+ === 2Cr3+ + 6Fe3+BacktitrationReactionCr2O72- + 6Fe2+ === 2Cr3+ + 6Fe3+vol=18.29mLM=0.00389Mmmol back titration = Fe2+ excess= (V*M) backtitration==0.0711481mmolmmol Fe total = mmol Fe-amm-sulfat=mass/Mr Fe-amm-sulfat=1.2760147507mmolmmol Fe2+ bereaksi dengan Cr2O7 sampel=1.2048666507mmolmmol Cr2O7= 1/6 * mmol Fe2+=0.2008111085mmolmmol Cr3+ = 2 x mmol Cr2O7=0.4016222169mmolmass Cr3+=20.8827889527mg=0.020882789gvol Cr3+= mass/density=0.0029003874cm3thickness=volume/area=0.0000966796cm=0.9667957848mMr Fe-amm-sulfat=391.85g/mol

48sample=0.4185g=418.5mgTitration Fe2+KMnO4Vol=41.27mLM=0.025MMol KMnO4= (M*V)=1.03175mmolReaction: 5 Fe2+ + KMnO4 === 5 Fe3+ + Mn2+mol Fe2+ = 5* mol KMnO4=5.15875mmolReaction: 2 Fe2+ === 2 Fe3+ ===== Fe2O3mol Fe2O3 = 0,5*mol Fe2+ =2.579375mmolmass Fe2O3= mol*Mr Fe2O3=412.7mg%Fe2O3= mass Fe2O3/mass sample*100%=98.61%

50Walden reductor: UO22+ --> U4+Addition of Fe3+: U4++ 2Fe3+ ---> U6+ + 2Fe2+ Titration: 6 Fe2+ + K2Cr2O7 --> 6 Fe3+ + 2 Cr3+sample=0.315g=315mgTitration:Vol=10.52mLM=0.00987Mmmol K2Cr2O7= (V*M)=0.1038324mmolmmol Fe2+ =6 * mmol K2Cr2O7=0.6229944mmolmmol U4+ =0,5 * mmol Fe2+ =0.3114972mmolmass U= mmol U4+ * Ar (U)=74.1453389841mg%U= mass U/mass sample *100=23.54%

Ar U=238.02891

51Cr=51.9961Fe55.845Area=30cm2density Cr=7.2g/cm3oxidizing: 2Cr3+ === Cr2O72-Addition of Fe(NH4)2(SO4)26H2O=500.0mgReactionCr2O72- + 6Fe2+ === 2Cr3+ + 6Fe3+BacktitrationReactionCr2O72- + 6Fe2+ === 2Cr3+ + 6Fe3+vol=18.29mLM=0.00389Mmmol back titration = Fe2+ excess= (V*M) backtitration==0.0711481mmolmmol Fe total = mmol Fe-amm-sulfat=mass/Mr Fe-amm-sulfat=1.2760147507mmolmmol Fe2+ bereaksi dengan Cr2O7 sampel=1.2048666507mmolmmol Cr2O7= 1/6 * mmol Fe2+=0.2008111085mmolmmol Cr3+ = 2 x mmol Cr2O7=0.4016222169mmolmass Cr3+=20.8827889527mg=0.020882789gvol Cr3+= mass/density=0.0029003874cm3thickness=volume/area=0.0000966796cm=0.9667957848mMr Fe-amm-sulfat=391.85g/mol

48sample=0.4185g=418.5mgTitration Fe2+KMnO4Vol=41.27mLM=0.025MMol KMnO4= (M*V)=1.03175mmolReaction: 5 Fe2+ + KMnO4 === 5 Fe3+ + Mn2+mol Fe2+ = 5* mol KMnO4=5.15875mmolReaction: 2 Fe2+ === 2 Fe3+ ===== Fe2O3mol Fe2O3 = 0,5*mol Fe2+ =2.579375mmolmass Fe2O3= mol*Mr Fe2O3=412.7mg%Fe2O3= mass Fe2O3/mass sample*100%=98.61%

50Walden reductor: UO22+ --> U4+Addition of Fe3+: U4++ 2Fe3+ ---> U6+ + 2Fe2+ Titration: 6 Fe2+ + K2Cr2O7 --> 6 Fe3+ + 2 Cr3+sample=0.315g=315mgTitration:Vol=10.52mLM=0.00987Mmmol K2Cr2O7= (V*M)=0.1038324mmolmmol Fe2+ =6 * mmol K2Cr2O7=0.6229944mmolmmol U4+ =0,5 * mmol Fe2+ =0.3114972mmolmass U= mmol U4+ * Ar (U)=74.1453389841mg%U= mass U/mass sample *100=23.54%

Ar U=238.02891

51Cr=51.9961Fe55.845Area=30cm2density Cr=7.2g/cm3oxidizing: 2Cr3+ === Cr2O72-Addition of Fe(NH4)2(SO4)26H2O=500.0mgReactionCr2O72- + 6Fe2+ === 2Cr3+ + 6Fe3+BacktitrationReactionCr2O72- + 6Fe2+ === 2Cr3+ + 6Fe3+vol=18.29mLM=0.00389Mmmol back titration = Fe2+ excess= (V*M) backtitration==0.0711481mmolmmol Fe total = mmol Fe-amm-sulfat=mass/Mr Fe-amm-sulfat=1.2760147507mmolmmol Fe2+ bereaksi dengan Cr2O72- sampel=1.2048666507mmolmmol Cr2O72-= 1/6 * mmol Fe2+=0.2008111085mmolmmol Cr3+ = 2 x mmol Cr2O72-=0.4016222169mmolmass Cr3+=20.8827889527mg=0.020882789gvol Cr3+= mass/density=0.0029003874cm3thickness=volume/area=0.0000966796cm=0.9667957848mMr Fe-amm-sulfat=391.85g/mol