Question

Calculate the ph of a buffer that is 0.94 mhc2h3o2 and 0.059 mnac2h3o2. the ka for hc2h3o2 is 1.8×10−5. calculate the of a buffer that is 0.94 and 0.059 . the for is . 2.86 3.54 4.74 1.80 5.97

Answer 1

The pH of the buffer is 3.54.

Step-by-step explanation:

To calculate the pH of acidic buffer, we use the equation given by Henderson Hasselbalch:

`pH=pK_a+\log(([salt])/([acid]))`

`pH=pK_a+\log(([NaHCO_3])/([H_2CO_3]))`

We are given:

`pK_a` = negative logarithm of acid dissociation constant of carbonic acid

`pK_a=-\log[K_a]=-\[1.8* 10^(-5)]=4.74`

`[NaC_2H_3O_2]=0.059 M`

`[HC_2H_3O_2]=0.94 M`

pH = ?

Putting values in above equation, we get:

`pH=4.74+\log((0.059 M)/(0.94))\\\\pH=3.537\approx 3.54`

The pH of the buffer is 3.54.