Assays that employ PERMANGANOMETRY

Hydrogen Peroxide (H2O2)

Cherry Juice for Malic Acid (C4H6O5)

Sodium Nitrite (NaNO2)

Assays that employ

PERMANGANOMETRY 3

Indirect Titration (with Preliminary Treatment)

Residual Titration

Other Assays of Permanganometry (2 categories)

• Precipitated calcium carbonate

• Precipitated manganese dioxide

• Dibasic calcium phosphate

• Titanium dioxide (with blank determination)

Other Assays of Permanganometry 4

• Indirect Titration (with Preliminary Treatment)

• Potassium permanganate tablets

• Lead oxide (with preliminary treatment)

Other Assays of Permanganometry 2

• Residual Titration

Direct Titration

Hydrogen Peroxide (H2O2) Type of titration:

Redox reaction

Hydrogen Peroxide (H2O2) Type:

H2O2

Hydrogen Peroxide (H2O2) Reducing agent (analyte)

KMnO4

Hydrogen Peroxide (H2O2) Oxidizing agent (titrant, volumetric solution)

H2SO4

Hydrogen Peroxide (H2O2) Acidifying agent, prevents formation of MnO2

3H2SO4 + 5H2O2 + 2KMnO4 → 2MnSO4 + K2SO4 + 5O2↑ + 8H2O

Hydrogen Peroxide (H2O2) Chemical reaction:

2; 2e-

Hydrogen Peroxide (H2O2) Factor (of analyte): because in the half-equation reaction of peroxide as a reducing agent in

acidic medium, it lost a total of ?

H2O2 → O2 + 2H+ + 2e-

iodine flask

suitable flask Hydrogen Peroxide (H2O2)

colorless to pale pink

Hydrogen Peroxide (H2O2) from _ → ?

ammonium hydroxide

alkalinize the solution and keep the calcium oxalate insoluble

filtration

filters off yung mga di nagreact

mallic acid

_ → calcium malate → caoxalate

calcium malate

mallic acid → _→ caoxalate

calcium oxalate

mallic acid → calcium malate → _

Indirect Titration

Cherry Juice for Malic Acid (C4H6O5) Type of titration:

Redox reaction

Cherry Juice for Malic Acid (C4H6O5) Type:

C4H6O5 (Malic acid)

Cherry Juice for Malic Acid (C4H6O5) Reducing agent (analyte)

KMnO4:

Cherry Juice for Malic Acid (C4H6O5) Oxidizing agent (titrant, volumetric solution)

H2SO4:

Cherry Juice for Malic Acid (C4H6O5) Acidifying agent, prevents formation of MnO2

CaCO3

Cherry Juice for Malic Acid (C4H6O5) reacts with C4H6O5 to form calcium malate (CaC2H6O5); its CO32- turned to CO2 gas (which was facilitated by heating)

Cherry Juice for Malic Acid (C4H6O5)

_ reacts with C4H6O5 to form calcium malate (CaC2H6O5); its CO32- turned to CO2 gas (which was facilitated by heating)

calcium malate (CaC2H6O5)

Cherry Juice for Malic Acid (C4H6O5) reacts with C4H6O5 to form _; its CO32- turned to CO2 gas (which was facilitated by heating)

CO2 gas

Cherry Juice for Malic Acid (C4H6O5) reacts with C4H6O5 to form calcium malate (CaC2H6O5); its CO3

2- turned to _

(which was facilitated by heating)

(NH4)2(C2O4)

Cherry Juice for Malic Acid (C4H6O5) converts CaC2H6O5 to calcium oxalate (CaC2O4) crystals (the form of malic acid titrated by KMnO4, instead of malic acid itself)

CaC2H6O5

Cherry Juice for Malic Acid (C4H6O5) converts _ to calcium oxalate (CaC2O4) crystals (the form of malic acid titrated by KMnO4, instead of malic acid itself)

calcium oxalate (CaC2O4) crystals

Cherry Juice for Malic Acid (C4H6O5) converts CaC2H6O5 to _ (the form of malic acid titrated by KMnO4, instead of malic acid itself)

NH4OH

Cherry Juice for Malic Acid (C4H6O5) maintains CaC2O4 insoluble by providing NH4+ to keep the reaction forward

malic acid

_is converted to calcium malate, and then finally to calcium oxalate

calcium malate

malic acid is converted to _, and then finally to calcium oxalate

calcium oxalate

malic acid is converted to calcium malate, and then finally to _

Cherry Juice for Malic Acid (C4H6O5)

colorless → pink

Sodium Nitrite (NaNO2)

contains 97.0-101.0% of NaNO2, calculated on the dried basis (USP)

(Double) Residual Titration

Sodium Nitrite (NaNO2) [Type of titration:

Redox reaction

Sodium Nitrite (NaNO2) Type:

NaNO2:

Sodium Nitrite (NaNO2) Reducing agent (analyte)

KMnO4:

Sodium Nitrite (NaNO2) Oxidizing agent (excess titrant, volumetric solution)

H2SO4:

Sodium Nitrite (NaNO2) Acidifying agent (prevents formation of MnO2)

H2C2O4:

Sodium Nitrite (NaNO2) Reducing agent (backtitrant)

3H2SO4 + 5NaNO2 + 2KMnO4 → 2MnSO4 + 5Na2NO3 + K2SO4 + 3H2O

3H2SO4 + 5H2C2O4.2H2O + 2KMnO4 → 2MnSO4 + 10CO2↑ + K2SO4 + 18H2O

Sodium Nitrite (NaNO2) Chemical reactions

2

Sodium Nitrite (NaNO2) Factor (of analyte): _ (because in the half-equation reaction of nitrite as a reducing agent in

acidic medium, it lost a total of 2e-.

%P formula

Indirect Titration (with Preliminary Treatment)

Residual Titration

Other Assays of Permanganometry 2

• Precipitated calcium carbonate

• Precipitated manganese dioxide

• Dibasic calcium phosphate

• Titanium dioxide (with blank determination)

Indirect Titration (with Preliminary Treatment) 4

• Potassium permanganate tablets

• Lead oxide (with preliminary treatment)

Residual Titration 2