LABORATORY 10 DETERMINATION OF VITAMIN C CONCENTRATION 3. How many grams of (pure) vitamin C is...
Calculate the cell potential for Ca(s) + Mn2+(aq) ↔ Ca2+(aq) + Mn(s). Assume any aqueous species has a concentration of 1 M. Ca2+(aq) + 2e- → Ca(s) Eº = -2.87 V Mn2+(aq) + 2e- → Mn(s) Eº = -1.18 V
What is the standard emf of a galvanic cell made of a Co electrode in a 1.0 M Co(NO32 solution and a Al electrode in a 1.0 M AI(NO3)3 solution at 25°C? 0 cell Standard Reduction Potentials at 25°C Half-Reaction E(V +2.87 +2.07 +1.82 O,(g) 2H (aq)2e0(g)+HO Co3+(aq) + e-_? Co2+(aq) H,02(aq) + 2H"(aq) + 2e-_ 2H20 Cu2+(aq) + 2e-? Cu(s) AgCIs) + Ag(s) + CI(a) S02-(aq) + 4H'(aq) + 2e S02(g) + 2H20 Cu2+(aq) + e-_ Cu+(aq) Sn (aq)...
Government and industry analysts routinely measure the quantity of ascorbic acid (vitamin C, C6H8O6) in commercial products such as fruit juices and vitamin tablets. The ascorbic acid reacts with excess iodine, and the amount of I2 remaining is determined with sodium thiosulfate (Na2S2O3). It is suspected by the Montreal Fraud Division that a prominent natural foods importer is defrauding his customers by claiming that his vitamin C tablets contain 45% of the active ingredient ascorbic acid. In one analysis, a...
Ascorbic acid or Vitamin C is a simple compound with the following chemical formula C6H8O6. Besides being an acid, it is also a reducing agent. One method for determining the amount of vitamin C in a sample is to titrate it with a solution of bromine, Br2, a good oxidizing agent based on the following chemical equation: Br2 (aq) + C6H8O6 (aq) --> 2HBr (aq) + C6H6O6 (aq) Suppose a 1.00-g “chewable” vitamin C tablet requires 27.85 mL of 0.102 M...
Ascorbic acid or Vitamin C is a simple compound with the following chemical formula C6H8O6. Besides being an acid, it is also a reducing agent. One method for determining the amount of vitamin C in a sample is to titrate it with a solution of bromine, Br2, a good oxidizing agent based on the following chemical equation: Br2 (aq) + C6H3O6 (aq) → 2HBr (aq) + C6H6O6 (aq) Suppose a 1.00-g “chewable” vitamin C tablet requires 27.85 mL of 0.102...
Standard reduction half-cell potentials at 25°C E (V) E (V) 1.50 -0.45 0.80 -0.50 0.77 -0.73 0.52 -0.76 0.34 -1.18 Half-reaction Aut (aq) + 3e +Au(s) Ag+ (aq) + +Ag(s) Fe3+ (aq) +34 Fo+ (aq) Cut(aq) + Cu(s) Cu²+ (aq) + 2e +Cu(s) 2H+ (aq) - 2e +H2 (6) Fe3+ (aq) + 3e Fe(s) Pb2+ (aq) + 2e →Pb(s) Sn-(aq) + 2e +Sn(s) Ni2+ (aq) + 2e →Ni(s) Co2(aq) +2e + Co(s) ca? (aq) + 2e +Cd(s) 0.00 Half-reaction Fe(aq)...
A) Use tabulated electrode potentials to calculate ΔG∘ for the reaction. 2K(s)+2H2O(l)→H2(g)+2OH−(aq)+2K+(aq) B) (Refer to the following standard reduction half-cell potentials at 25∘C: VO2+(aq)+Ni2+(aq)2H+(aq)++2e−e−→ →Ni(s)VO2+(aq) +H2O(l)E∘=−0.23V E∘=0.99V) An electrochemical cell is based on these two half-reactions: Oxidation:Reduction:Ni(s)VO2+(aq,0.024M)+2H+(aq,1.4M)+e−→→Ni2+(aq,1.8M)+2e−VO2+(aq,1.8M)+H2O(l) Calculate the cell potential under these nonstandard concentrations. C) Standard reduction half-cell potentials at 25∘C Half-reaction E∘ (V ) Half-reaction E∘ (V ) Au3+(aq)+3e−→Au(s) 1.50 Fe2+(aq)+2e−→Fe(s) − 0.45 Ag+(aq)+e−→Ag(s) 0.80 Cr3+(aq)+e−→Cr2+(aq) − 0.50 Fe3+(aq)+3e−→Fe2+(aq) 0.77 Cr3+(aq)+3e−→Cr(s) − 0.73 Cu+(aq)+e−→Cu(s) 0.52 Zn2+(aq)+2e−→Zn(s) − 0.76...
Use the tabulated electrode potentials to calculate K for the oxidation of nickel by H+: Ni(s)+2H+(aq)→Ni2+(aq)+H2(g) Express your answer using two significant figures. Standard reduction half-cell potentials at 25∘C Half-reaction E∘ (V) Half-reaction E∘ (V) Au3+(aq)+3e−→Au(s) 1.50 Fe2+(aq)+2e−→Fe(s) −0.45 Ag+(aq)+e−→Ag(s) 0.80 Cr3+(aq)+e−→Cr2+(aq) −0.50 Fe3+(aq)+3e−→Fe2+(aq) 0.77 Cr3+(aq)+3e−→Cr(s) −0.73 Cu+(aq)+e−→Cu(s) 0.52 Zn2+(aq)+2e−→Zn(s) −0.76 Cu2+(aq)+2e−→Cu(s) 0.34 Mn2+(aq)+2e−→Mn(s) −1.18 2H+(aq)+2e−→H2(g) 0.00 Al3+(aq)+3e−→Al(s) −1.66 Fe3+(aq)+3e−→Fe(s) −0.036 Mg2+(aq)+2e−→Mg(s) −2.37 Pb2+(aq)+2e−→Pb(s) −0.13 Na+(aq)+e−→Na(s) −2.71 Sn2+(aq)+2e−→Sn(s) −0.14 Ca2+(aq)+2e−→Ca(s) −2.76 Ni2+(aq)+2e−→Ni(s) −0.23 Ba2+(aq)+2e−→Ba(s) −2.90 Co2+(aq)+2e−→Co(s) −0.28 K+(aq)+e−→K(s) −2.92 Cd2+(aq)+2e−→Cd(s)...
Fill in the Blanks Ered (V) 0.68 0.52 0.40 0.34 0.16 0 Half Reaction Ered (V) Half Reaction F2+2e →2F 2.87 02 + 2H+ 2e →H,O, Ag?+ e → Ag 1.99 Cute → Cu Code → CO2 1.82 O2 + 2H,0 + 4e → 40H H,02 + 2H+ + 2e → 2H,0 1.78 Cu2+ + 2e → Cu Ce+ + → Ce+ 1.70 Cu2+ e → Cu PbO, + 4H* +502 +2e → PbSO4 + 2H,0 1.69 2H*+2e → H2...
Standard Electrode Potentials at 25?C Reduction Half-Reaction E?(V) F2(g)+2e? ?2F?(aq) 2.87 Au3+(aq)+3e? ?Au(s) 1.50 Cl2(g)+2e? ?2Cl?(aq) 1.36 O2(g)+4H+(aq)+4e? ?2H2O(l) 1.23 Br2(l)+2e? ?2Br?(aq) 1.09 NO3?(aq)+4H+(aq)+3e? ?NO(g)+2H2O(l) 0.96 Ag+(aq)+e? ?Ag(s) 0.80 I2(s)+2e? ?2I?(aq) 0.54 Cu2+(aq)+2e? ?Cu(s) 0.16 2H+(aq)+2e? ?H2(g) 0 Cr3+(aq)+3e? ?Cr(s) -0.73 2H2O(l)+2e? ?H2(g)+2OH?(aq) -0.83 Mn2+(aq)+2e? ?Mn(s) -1.18 How can the table be used to predict whether or not a metal will dissolve in HCl? In HNO3? Drag the terms on the left to the appropriate blanks on the right to...