A buffer is made up of 239mL of 0.187 M potassium hydrogen tartrate (K2HC4H4O6) and 137mL of 0.288 M potassium tartrate (K2C4H4O6). Ka for (H2C4H4O6) is 4.55 x 10-5. Assuming volumes are additive, calculate: (a) the pH of the buffer (b) the pH of the buffer after adding 0.025 mol HCL to 0.376 L of the buffer. (c) the pH of the buffer after adding 0.025 mol KOH to 0.376 L of the buffer
A buffer is made up of 239mL of 0.187 M potassium hydrogen tartrate (K2HC4H4O6) and 137mL of 0.288 M potassium tartrate (K2C4H4O6). Ka for (H2C4H4O6) is 4.55 x 10-5. Assuming volumes are additive, calculate:
(a) the pH of the buffer
(b) the pH of the buffer after adding 0.025 mol HCL to 0.376 L of the buffer.
(c) the pH of the buffer after adding 0.025 mol KOH to 0.376 L of the buffer
A buffer solution resists changes in pH. pH <7 has an acidic buffer solution; pH>7 has a basic buffer solution.
For a more acidic solution, the concentration of will be more, pH will be less and vice versa for a less acidic solution. i.e. a measure of acidity of a solution. pOH is a measure of alkalinity of a solution. For a more basic solution, pOH will be more.
The pH of a buffer solution depends on the ratio of rather than on the concentration of acid or base alone. Then the exact ratio of for a desired pH is determined from value and from the Henderson-Hasselbach equation. this equation shows the relationship between pH of a solution, the acid dissociation constant and the concentration of acidic ions and the neutral molecule in solution. It is represented as:
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