pH Buffering Systems

Applied Environmental Chemistry
 

  

Buffer Solution Formulas

The following formulas produce buffers with pH values close to that indicated.

The weights give 0.1 M concentrations of each species, when diluted to 1.0 L, so that the [acid]:[conjugate base] ratio is unity. In most cases the pH will have to be adjusted using a pH meter and the dropwise addition of either 6 M HCl or 6M NaOH to one liter of solution.
 



Training Course in Basic Water Analysis and Wastewater Analysis
 

Acid, formula and wt.or volume of standard reagent (mL) Conjugate base, formula and wt. pH
Phosphoric acid 85% H3PO4
6.8 mL
Monopotassium phosphate, KH2PO4
12.8 g
2.1
Hydrochloric acid, HCl, 8.6 mL Potassium hydrogen phthalate, KHC8H4O4, 20.4 g 2.8
Citric acid, HOC(CH2CO2H)2CO2H, 19.2 g monopotassium citrate, HOC(CH2CO2H)2CO2K, 23.0 g 3.1
Methyl succinic acid, HO2CCH2CH2CO2H, 11.8 Monosodium methylsuccinate,

HO2CCH2CH2CO2Na, 14.0

4.1
Acetic acid,CH3CO2H, glacial, 5.7 mL, or
Acetic acid,CH3CO2H, dilute (36%), 15.9 mL
Sodium acetate,CH3CO2Na , 
8.2 g
4.75
Potassium hydrogen phthalate, KHC8H4O4, 20.4 g, sodium hydroxide, NaOH, 4.0 g 4.8
Monosodium methylsuccinate, NaO2CCH2CH(CH3)CO2H, 15.3 g Disodium methylsuccinate, NaO2CCH2CH(CH3)CO2Na, 17.5 g 5.6
Monosodium citrate, HOC(CH2CO2H)2CO2Na, 21.4 g Disodium citrate, NaOC(CH2CO2H)2CO2Na, 23.6 g 5.9
Disodium citrate, HOC(CH2CO2Na)2CO2H, 23.6 g Trisodium citrate, HOC(CH2CO2Na)2CO2Na, 25.8 g 6.4
Monopotassium phosphate, KH2PO4,

12.8 g

Dipotassium phosphate, K2HPO4

15.8 g

7.2
DL-Cysteine, HSCH2CH(NH2)CO2H, 12.1 g Sodium DL-Cysteinate, HSCH2CH(NH2)CO2Na, 14.3 g 8.1
Boric acid

H2B4O7, 31.4 g

Sodium Hydroxide, NaOH, 4.0 g 9.1
Sodium bicarbonate, NaHCO3, 8.4 g Sodium carbonate, Na2CO3, 10.6 g 10.2
Monosodium tellurate, NaHTeO4, 21.6g Disodium tellurate, Na2TeO4, 23.8g 11.3
Monosodium ascorbate, NaC6H7O6, 19.8g Disodium ascorbate, Na2C6H7O6, 22.0g 11.8
Dipotassium phosphate, K2HPO4

15.8 g

Tripotassium phosphate, K3PO4

19.6 g

12.7
Boric acid

H2B4O7, 31.4 g

Sodium hydroxide, NaOH, 12.0 g 12.7

New Online Training Courses for Professionals
LEED- AP / Green Associate Training/ Professional Development Hours Courses
Alternative Energy and Green Technologies>
 Health and Safety Training - Chemical Handling and Disposal
 Water, Wastewater, and Stormwater Design, Operation, and Management