Calculate the pH of a sodium acetate- acetic acid buffer solution (Ka= 1.78 x 10 raised to power (-5) in which the concentration of both components is 1 M. 

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jerichorayel | College Teacher | (Level 2) Senior Educator

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To get the pH of the buffer solution, we should use the Henderson-Hasselbalch equation which states that:

`pH = pK_a + log (([A^-])/([HA]))`

If both components have the the concentration of 1M then:

 

`pH = pK_a + log (([1M])/([1M]))`

`pH = pK_a + log (1)`

**log(1) = 0

`pH = pk_a`  

 

`k_a = 1.78x10^(-5)`

`pk_a = -log (k_a)`

`pH = pk_a`

`pH = -log (1.78^(-5))`

pH = 1.25

 

 

Sources:

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