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Chemistry/Making Buffers
From WikiEducator
PREPARATION OF BUFFER SOLUTIONS
Dilute each of the mixtures to 1 L with distilled water. (NOTE: the pH will not be affected if the volumes are slightly more or less than 1 L.)
IMPORTANT: The pH of each buffer must be checked and adjusted before being bottled.
- If the pH is too high, adjust the pH to the correct value by adding 1 M HCl, with stirring.
- If the pH is too low, adjust the pH to the correct value by adding 1 M NaOH, with stirring.
| pH | Mixture |
|---|---|
| 3 | 10.21 g of potassium hydrogen phthalate + 223 mL of 0.10 M HCl |
| 4 | 10.21 g of potassium hydrogen phthalate + 1 mL of 0.10 M HCl |
| 5 | 10.21 g of potassium hydrogen phthalate + 226 mL of 0.10 M NaOH |
| 6 | 6.81 g of potassium phosphate monobasic + 56 mL of 0.10 M NaOH |
| 7 | 6.81 g of potassium phosphate monobasic + 291 mL of 0.10 M NaOH |
| 8 | 6.81 g of potassium phosphate monobasic + 467 mL of 0.10 M NaOH |
| 9 | 4.77 g of sodium tetraborate + 46 mL of 0.10 M HCl |
| 10 | 4.77 g of sodium tetraborate + 183 mL of 0.10 M NaOH |
| 11 | 2.10 g of sodium bicarbonate + 227 mL of 0.10 M NaOH |
