Question

Question #2c8ae

Answer 1

`[H^+]=7.58xx10^(-6)M`

Explanation:

We console this question using Henderson-Hasselbalch equation:

`pH=pK_a+log(([C_2H_3O_2^-])/([HC_2H_3O_2]))`

`pK_a=-logK_a=-log(1.8xx10^(-5))=4.74`

`=>pH=4.74+log((0.48)/(0.2))=5.12`

Now we can calculate the concentration of `H^+` by:

`[H^+]=10^(-pH)=10^(-5.12)=7.58xx10^(-6)M`

Here is a video that explains Henderson-Hasselbalch equation:
Acid - Base Equilibria | Buffer Solution.