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PilotLPTM [1.2K]
3 years ago
5

What is the pH of a 0.1 M phosphate buffer (pKa = 6.86) that contains equal amounts of acid and conjugate base?

Chemistry
1 answer:
Anvisha [2.4K]3 years ago
4 0

Answer : The pH of a 0.1 M phosphate buffer is, 6.86

Explanation : Given,

pK_a=6.86

Concentration of acid = 0.1 M

Concentration of conjugate base (salt) = 0.1 M

Now we have to calculate the pH of buffer.

Using Henderson Hesselbach equation :

pH=pK_a+\log \frac{[Salt]}{[Acid]}

Now put all the given values in this expression, we get:

pH=6.86+\log (\frac{0.1}{0.1})

pH=6.86

Therefore, the pH of a 0.1 M phosphate buffer is, 6.86

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Answer:

The catalyzed reaction will take 2.85 seconds to occur.

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t_{2} = t_{1}\frac{k_{1}}{k_{2}} = 6900 y*1.31 \cdot 10^{-11} = 9.04 \cdot 10^{-8} y*\frac{365 d}{1 y}*\frac{24 h}{1 d}*\frac{3600 s}{1 h} = 2.85 s

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