CH 3 COOH aq H aq CH 3 COO aq However all the calculated dissociation constant

Ch 3 cooh aq h aq ch 3 coo aq however all the

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CH 3 COOH (aq) H + (aq) + CH 3 COO - (aq) However, all the calculated dissociation constant values are close to each other and are all slightly above the accepted value, possibly because the higher K a indicates that there was more dissociation of HA. The values of pH calculated differed across the solutions, with the 1.0 M HA solution having a pH of 2.34, the buffer with 25.0mL 1.0M NaA having a pH of 4.95, and the buffer with 5.0mL NaA having a pH of 3.81. The addition of the sodium acetate is not intended to largely change the pH, as that is the intention of a buffer. However, the trend does show that the more sodium acetate is added, the more basic the pH. The measured pH and the calculated
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pH for the buffers were very close with errors less than 4%. Both measured pHs are lower than that of the calculated, possibly because the solution was not thoroughly mixed. In part three, a strong base and strong acid were added to a buffered and unbuffered solution. The unbuffered solution showed a huge change in pH when the strong acid and base were added, but the buffered solution showed resistance to change. The measured and calculated
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