Redox Titrations A redox titration is the same

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Redox Titrations A redox titration is the same as an acid-base titration except it

Redox Titrations A redox titration is the same as an acid-base titration except it involves a redox reaction and generally does not require an indicator. Reagents are chosen so that the reaction is spontaneous and one of the half reactions has a natural colour change.

Redox Titrations A redox titration is the same as an acid-base titration except it

Redox Titrations A redox titration is the same as an acid-base titration except it involves a redox reaction and generally does not require an indicator. Reagents are chosen so that the reaction is spontaneous and one of the half reactions has a natural colour change. Pick a suitable reagent for redox titration involving IO 3 - in acid solution. FISO 42 Cl-

Pick the spontaneous reaction

Pick the spontaneous reaction

6. 75 m. L of 0. 100 M KMn. O 4 is required to

6. 75 m. L of 0. 100 M KMn. O 4 is required to titrate 25. 0 m. L of Fe. Cl 2. Calculate the [Fe 2+]. Mn. O 4 - + 8 H+ + 5 Fe 2+ → Mn 2+ + 4 H 2 O + 5 Fe 3+

6. 75 m. L of 0. 100 M KMn. O 4 is required to

6. 75 m. L of 0. 100 M KMn. O 4 is required to titrate 25. 0 m. L of Fe. Cl 2. Calculate the [Fe 2+]. Mn. O 4 - + 8 H+ + 5 Fe 2+ → Mn 2+ + 4 H 2 O 0. 00675 L 0. 0250 L 0. 100 M ? M + 5 Fe 3+

6. 75 m. L of 0. 100 M KMn. O 4 is required to

6. 75 m. L of 0. 100 M KMn. O 4 is required to titrate 25. 0 m. L of Fe. Cl 2. Calculate the [Fe 2+]. Mn. O 4 - + 8 H+ + 5 Fe 2+ → Mn 2+ + 4 H 2 O 0. 00675 L 0. 0250 L 0. 100 M ? M [Fe 2+] = + 5 Fe 3+

6. 75 m. L of 0. 100 M KMn. O 4 is required to

6. 75 m. L of 0. 100 M KMn. O 4 is required to titrate 25. 0 m. L of Fe. Cl 2. Calculate the [Fe 2+]. Mn. O 4 - + 8 H+ + 5 Fe 2+ → Mn 2+ + 4 H 2 O 0. 00675 L 0. 0250 L 0. 100 M ? M [Fe 2+] = + 5 Fe 3+

6. 75 m. L of 0. 100 M KMn. O 4 is required to

6. 75 m. L of 0. 100 M KMn. O 4 is required to titrate 25. 0 m. L of Fe. Cl 2. Calculate the [Fe 2+]. Mn. O 4 - + 8 H+ + 5 Fe 2+ → Mn 2+ + 4 H 2 O 0. 00675 L 0. 0250 L 0. 100 M ? M 0. 00675 L Mn. O 4 - x [Fe 2+] = 0. 100 mole 1 L + 5 Fe 3+

6. 75 m. L of 0. 100 M KMn. O 4 is required to

6. 75 m. L of 0. 100 M KMn. O 4 is required to titrate 25. 0 m. L of Fe. Cl 2. Calculate the [Fe 2+]. 1 Mn. O 4 - + 8 H+ +5 Fe 2+ → Mn 2+ + 4 H 2 O + 0. 00675 L 0. 0250 L 0. 100 M ? M 0. 00675 L Mn. O 4 - x [Fe 2+] = 0. 100 mole 1 L x 5 Fe 3+ 5 moles Fe 2+ 1 mole Mn. O 4 -

6. 75 m. L of 0. 100 M KMn. O 4 is required to

6. 75 m. L of 0. 100 M KMn. O 4 is required to titrate 25. 0 m. L of Fe. Cl 2. Calculate the [Fe 2+]. Mn. O 4 - + 8 H+ + 5 Fe 2+ → Mn 2+ + 4 H 2 O 0. 00675 L 0. 0250 L 0. 100 M ? M 0. 00675 L Mn. O 4 - x [Fe 2+] = 0. 100 mole 1 L 0. 0250 L + x 5 Fe 3+ 5 moles Fe 2+ 1 mole Mn. O 4 -

6. 75 m. L of 0. 100 M KMn. O 4 is required to

6. 75 m. L of 0. 100 M KMn. O 4 is required to titrate 25. 0 m. L of Fe. Cl 2. Calculate the [Fe 2+]. Mn. O 4 - + 8 H+ + 5 Fe 2+ → Mn 2+ + 4 H 2 O 0. 00675 L 0. 0250 L 0. 100 M ? M 0. 00675 L Mn. O 4 - x [Fe 2+] = 0. 100 mole 1 L 0. 0250 L = 0. 135 M + x 5 Fe 3+ 5 moles Fe 2+ 1 mole Mn. O 4 -

Write the anode and cathode reactions. voltmeter Pt Pt Na. NO 3 aq) Inert

Write the anode and cathode reactions. voltmeter Pt Pt Na. NO 3 aq) Inert electrodes- look at the solution for the reactions Mn. O 4 - in acid H 2 O 2(aq)

Cathode Anode

Cathode Anode

Cathode: Anode: Mn. O 4 H 2 O 2 + 8 H+ + 5

Cathode: Anode: Mn. O 4 H 2 O 2 + 8 H+ + 5 e→ O 2 → + 2 H+ What happens to the mass of the cathode? Constant What happens to the mass of the anode? Constant What happens to the p. H of the cathode? Increases What happens to the p. H of the anode? Decreases Mn 2+ + 4 H 2 O + 2 e-

Non-Inert Electrodes A non-inert Anode might oxidize. The Cathode will stay inert. DC Power

Non-Inert Electrodes A non-inert Anode might oxidize. The Cathode will stay inert. DC Power - + Cu Cu 2 K+ SO 42 H 2 O K 2 SO 4(aq)

Non-Inert Electrodes A non-inert Anode might oxidize. The Cathode will stay inert. DC Power

Non-Inert Electrodes A non-inert Anode might oxidize. The Cathode will stay inert. DC Power - + Cu Cu 2 K+ SO 42 H 2 O K 2 SO 4(aq)

Non-Inert Electrodes A non-inert Anode might oxidize. The Cathode will stay inert. DC Power

Non-Inert Electrodes A non-inert Anode might oxidize. The Cathode will stay inert. DC Power - + Cu Cu Cathode 2 K+ Reduction SO 42 H 2 O K 2 SO 4(aq)

Non-Inert Electrodes A non-inert Anode might oxidize. The Cathode will stay inert. DC Power

Non-Inert Electrodes A non-inert Anode might oxidize. The Cathode will stay inert. DC Power - + Cu Cu Cathode 2 K+ Reduction SO 42 - 2 H 2 O + 2 e-→H 2 +2 OH- H 2 O -0. 41 v K 2 SO 4(aq)

Non-Inert Electrodes A non-inert Anode might oxidize. The Cathode will stay inert. DC Power

Non-Inert Electrodes A non-inert Anode might oxidize. The Cathode will stay inert. DC Power - + Cu Cu - Cu might oxidize Cathode 2 K+ Reduction SO 42 - 2 H 2 O + 2 e-→H 2 +2 OH- H 2 O -0. 41 v K 2 SO 4(aq)

You must look at the possible oxidation of: SO 42 H 2 O Cu

You must look at the possible oxidation of: SO 42 H 2 O Cu Strongest Reducing Agent

Non-Inert Electrodes A non-inert Anode might oxidize. The Cathode will stay inert. DC Power

Non-Inert Electrodes A non-inert Anode might oxidize. The Cathode will stay inert. DC Power - + Cu Cu + Cathode 2 K+ Reduction 2 H 2 →H 2(g)+ O+2 e- -0. 41 v SO 422 OH- H 2 O K 2 SO 4(aq) Anode Oxidation Cu(s) → Cu 2++2 e-0. 34 v

Non-Inert Electrodes A non-inert Anode might oxidize. The Cathode will stay inert. DC Power

Non-Inert Electrodes A non-inert Anode might oxidize. The Cathode will stay inert. DC Power - + Cu Cu + Cathode 2 K+ Reduction 2 H 2 →H 2(g)+ O+2 e- -0. 41 v SO 422 OH- H 2 O Anode Oxidation Cu(s) → Cu 2++2 e-0. 34 v K 2 SO 4(aq) 2 H 2 O + Cu(s) → Cu 2++ H 2 +2 OH- E 0 = -0. 75 v MTV = +0. 75 v

Is Al a reactive or non-reactive metal? Look on page 8 Reactive as Al

Is Al a reactive or non-reactive metal? Look on page 8 Reactive as Al is a relatively strong reducing agent. Why is Al used for boats, patio furniture, swing sets, and trucks boxes? Al makes a clear transparent Al 2 O 3 paint like coating that prevents further oxidation.