Calculate the pH of a 0.47 M solution of LiC2H3O2
What is the pH of a 0.47 M solution of LiC2H3O2 and how can it be calculated?
The pH of a 0.47 M solution of LiC2H3O2 can be calculated using the dissociation constant (Ka) of HC2H3O2. The pH of the solution is approximately 8.46. To calculate the pH of the solution, we need to consider the dissociation of LiC2H3O2 in water. LiC2H3O2 is a salt formed by the reaction of lithium hydroxide (LiOH) and acetic acid (HC2H3O2). The acetate ion (C2H3O2-) acts as a weak base in water, and the concentration of the acetate ion affects the pH of the solution.
Calculation Steps:
Concentration of LiC2H3O2 = 0.47 M
Dissociation constant (Ka) of HC2H3O2 = 1.8 x 10^-5
1. Write the balanced equation for the dissociation of HC2H3O2:
HC2H3O2 ⇌ H+ + C2H3O2-
2. Set up an ICE (Initial, Change, Equilibrium) table to determine the concentration of H+ ions and C2H3O2- ions at equilibrium. Assume that the initial concentration of H+ is 0 and the initial concentration of C2H3O2- is equal to the concentration of LiC2H3O2.
HC2H3O2 ⇌ H+ + C2H3O2-
Initial: 0.47 M 0 0
Change: -x +x +x
Equilibrium: 0.47 M - x x x
3. Substitute the equilibrium concentrations into the expression for the dissociation constant (Ka):
Ka = [H+][C2H3O2-] / [HC2H3O2]
Plugging in the values:
1.8 x 10^-5 = (x)(x) / (0.47 - x)
4. Simplify the expression and solve for x using the quadratic equation. The value of x will represent the concentration of H+ ions.
5. Calculate the pH using the formula:
pH = -log[H+]
After performing the calculations, we find that the pH of the 0.47 M solution of LiC2H3O2 is approximately 8.46.