Standardization buffersFor pH=7.00 :Add 29.1 ml of 0.1 molar NaOH to 50 ml 0.1 molar potassium dihydrogen phosphate.

Alternatively :Dissolve 1.20g of sodium dihydrogen phosphate and 0.885g of disidium hydrogen phosphate in 1 liter volume distilled water.

For pH= 4.00 :Add 0.1 ml of 0.1 molar NaOH to 50 ml of 0.1 molar potassium hydrogen phthalate .

Alternatively :Dissolve 8.954g of disodium hydrogen phosphste.12 H2O and 3.4023g of potassium dihydrogen phosphate in 1 liter volume distilled water.

Range of common buffer systems

Buffering systemUseful buffering pH range @ 25C

Hydrochloric acid/ Potassium chloride1.0 - 2.2

Glycine/ Hydrochloric acid2.2 - 3.6

Potassium hydrogen phthalate/ Hydrochloric acid2.2 - 4.0

Citric acid/ Sodium citrate3.0 - 6.2

Sodium acetate/ Acetic acid3.7 - 5.6

Potassium hydrogen phtaalate/ Sodium hydroxide4.1 - 5.9

Disodium hydrogen phthalate / Sodium dihydrogen orthophospate5.8 - 8.0

Dipotassium hydrogen phthalate / Potassium dihydrogen orthophospate5.8 - 8.0

Potassium dihydrogen orthophosphate / sodium hydroxide5.8 - 8.00

Barbitone sodium / Hydrochloric acid6.8 - 9.6

Tris (hydroxylmethyl) aminomethane / Hydrochloric acid7.0 - 9.00

Sodium tetraborate/ Hydrochloric acid8.1 - 9.2

Glycine/ Sodium hydroxide8.6 - 10.6

Sodium carbonate/ Sodium hydrogen carbonate9.2 - 10.8

Sodium tetraborate/ Sodium hydroxide9.3 - 10.7

Sodium bicarbonate / Sodium hydroxide9.60 - 11.0

Sodium hydrogen orthophosphate / Sodium hydroxide11.0 - 11.9

Potassium chloride/ Sodium hydroxide12.0 - 13.0

Preparing a Buffer SolutionThis page gives tabulated info on the preparation of buffers by mixing adjusterswith a known volume of the primary salt solution, and made up to 200ml with distilled water.

BUFFERS 1.00 - 9.00Buffer A :pH 1.0 - 2.2Buffer B :pH 2.2 - 4.00Buffer C :pH 4.10 - 5.90Buffer D :pH 5.8 - 8.00Buffer E :pH 7.0 - 9.00

50 ml 0.2 M KCl + mls of 0.2 M HCl100 ml 0.1 M potassium hydrogen phthalate + mls of 0.1 M HCl.100 ml 0.1 M potassium hydrogen phthalate + mls of 0.1 M NaOH. 100 ml 0.1 M KH2PO4 + mls of 0.1 M NaOH.100 ml 0.1 M tris (hydroxymethyl) aminomethane + mls of 0.1 M HCl.

pHmls of 0.2M HCl addedpHmls of 0.1M HCl addedpHmls of 0.1M NaOH addedpHmls of 0.1M NaOH addedpHmls of 0.1 M HCl added

1.00134.02.2099.04.102.65.807.27.0093.2

1.10105.62.3091.64.206.05.909.27.1091.4

1.2085.02.4084.44.309.46.0011.27.2089.4

1.3067.22.5077.64.4013.26.1013.67.3086.8

1.4053.22.6070.84.5017.46.2016.27.4084.0

1.5041.42.7064.24.6022.26.3019.47.5080.6

1.6032.42.8057.84.7027.26.4023.27.6077.0

1.7026.02.9051.44.8033.06.5027.87.7073.2

1.8020.43.0044.64.9038.86.6032.87.8069.0

1.9016.23.1037.65.0045.26.7038.67.9064.0

2.0013.03.2031.45.1051.06.8044.88.0058.4

2.1010.23.3025.85.2057.66.9051.88.l052.4

2.207.83.4020.85.3063.27.0058.28.2045.8

3.5016.45.4068.27.1064.28.3039.8

3.6012.65.5073.27.2069.48.4034.4

3.709.05.6077.67.3074.08.5029.4

3.805.85.7081.27.4078.28.6024.4

3.902.85.8084.67.5082.28.7020.6

4.000.25.9087.47.6085.68.8017.0

7.7088.48.9014.0

7.8090.69.0011.4

7.9092.2

8.0093.4

BUFFERS 08 - 13Buffer F: pH 8.0 - 9.10Buffer G :pH 9.2 - 10.80Buffer H :pH 9.60 - 11.00Buffer I :pH 10.90 - 12.00Buffer J :pH 12.00 - 13.00

100 mL 0.025 M Na2B4O7.10H2O (borax) + mls of 0.1 M HCl.100 mL 0.025 M Na2B4O7.10H2O (borax) + mls of 0.1 M NaOH.100 mL 0.05 M NaHCO3 + mls of 0.1 M NaOH.100 mL 0.05 M Na2HPO4 + mls of 0.1 M NaOH.50 mL 0.2 M KCl + volume indicated (in mL) 0.2 M NaOH.

pHmls of 0.1M HCl addedpHmls of 0.1M NaOH addedpHmls of 0.1M NaOH addedpHmls of 0.1M NaOH addedpHmls of 0.2M NaOH added

8.0041.09.201.89.6010.010.906.612.0012.0

8.1039.49.307.29.7012.411.008.212.1016.0

8.2037.69.4012.49.8015.211.1010.212.2020.4

8.3035.49.5017.69.9018.211.2012.612.3025.6

8.4033.29.6022.210.0021.411.3015.212.4032.4

8.5030.49.7026.210.1024.411.4018.212.5040.8

8.6027.09.8030.010.2027.611.5022.212.6051.2

8.7023.29.9033.410.3030.411.6027.012.7064.4

8.8019.210.0036.610.4033.011.7032.412.8082.4

8.9014.210.1039.010.5035.611.8038.812.90106.0

9.009.210.2041.010.6038.211.9046.013.00132.0

9.104.010.3042.610.7040.412.0053.8

10.4044.210.8042.4

10.5045.410.9044.0

10.6046.611.0045.4

10.7047.6

10.8048.5

Acetate buffer solutions pH 3 - 6

Make up the following solutions(1) 0.1M acetic acid(2) 0.1M sodium acetate (tri-hydrate) (13.6g / l)Mix in the following proportions to get the required ph

phvol. of 0.1Macetic acidvol. of 0.1Msodium acetate

3982.3 mls17.7 mls

4847.0 mls153.0 mls

5357.0 mls643.0 mls

652.2 mls947.8 mls

Phosphate buffer solutions ph 7 - 11

Make up the following solutions(1) 0.1M disodium hydrogen phosphate (14.2g / l)(2) 0.1M HCl(3) 0.1M NaOHMix in the following proportions to get the required phphvol. of phosphatevol. of 0.1M HClvol. of 0.1M NaOH

7756.0 mls244 mls

8955.1 mls44.9 mls

9955.0 mls45.0 mls

10966.4 mls

11965.3 mls

Addition of acid or base to a salt pH 3 - 11Here, the primary salt is a solid and is weighed out in grams. A measured amount of 0.1M HCl or NaOH is added,then made up to 1 liter to give the relevant buffer solution4.pHSalt mixtureDilute each mixture to 1 liter solution with distilled water

310.21g potassium hydrogen phthalate and 223ml of 0.10M HCl

410.21g potassium hydrogen phthalate and 1ml of 0.10M HCl

510.21g potassium hydrogen phthalate and 226ml of 0.10M NaOH

66.81g potassium dihydrogen phOsphate and 56ml of 0.10M NaOH

76.81g potassium dihydrogen phosphate and 291ml of 0.10M NaOH

86.81g potassium dihydrogen phosphate and 467ml of 0.10M NaOH

94.77g sodium tetraborate and 46ml of 0.10M HCl

104.77g sodium tetraborate and 183ml of 0.10M NaOH

112.10g sodium bicarbonate and 227ml of 0.10M NaOH