Asolution prepared by dissolving 0.100 mole of propionic acid in enough water to make 1.00 l of solution is observed to have a ph = 2.94. what is the ka for propionic acid? (a) 1.3 x 10¯6(b) 1.1 x 10¯3(c) 1.3 x 10¯5(d) 1.1 x 10¯2

C)

Explanation:

pH is defined as the negative logarithm of the concentration of hydrogen ions.

Thus,  

pH = - log [H⁺]

The expression of the pH of the calculation of weak acid is:-

Where, C is the concentration = 0.5 M

Given, pH = 2.94

Moles = 0.100 moles

Volume = 1.00 L

So,

C = 0.100 M