contestada

Calculate the ph of a solution that is 0.295 m in sodium formate (nahco2) and 0.205 m in formic acid (hco2h). the ka of formic acid is 1.77 ⋅ 10-4.

Respuesta :

mixter17
Hello!

The chemical reaction for the dissociation of Formic Acid is the following:

HCOOH + H₂O ⇄ HCOO⁻ + H₃O⁺

From this reaction we can use the Henderson-Hasselbach equation to find the pH, but first we need to find the value for the pKa:

pKa=-log(Ka)=3,75

pH=pKa + log([HCOO⁻]/[HCOOH])

pH=3,75 + log (0,295/0,205)

pH= 3,90

Have a nice day!

The pH of a solution that is 0.295 M in sodium formate and 0.205 M in formic acid is 3.90.

How do we calculate pH?

pH of the weak acid will be calculated by using the Henderson Hasselbalch equation as:

pH = pKa + log[Conjugate base] / [weak acid]

Given that:

Ka of the formic acid = 1.77 × 10⁻⁴

pKa = -log(Ka) = 3.75

Concentration of sodium formate = 0.295M

Concentration of formic acid = 0.205M

On putting all these values on the above equation, we get

pH = 3.75 + log(0.295/0.205)

pH = 3.90

Hence required value of pH is 3.90.

To know more about Henderson Hasselbalch equation, visit the below link:

https://brainly.com/question/13651361

Otras preguntas