Let's Calculate the pH of Benzoic Acid Solution!
What is the pH of a 0.0050 mol/l solution of benzoic acid?
Can you find the pH value for a solution with a given concentration of benzoic acid and Ka value?
Answer:
The pH of a 0.0050 M solution of benzoic acid is 3.75.
To calculate the pH of a 0.0050 M solution of benzoic acid, we need to use the equilibrium expression for the ionization of benzoic acid and the given Ka value. By setting up an ICE table and solving for x, we can determine the concentration of H+ ions at equilibrium and then convert it to pH using the equation pH = -log[H+].
Here's a step-by-step guide:Step 1: Write the balanced chemical equation for the ionization of benzoic acid: C6H5COOH (aq) <-> C6H5COO- (aq) + H+ (aq)
Step 2: Set up an ICE table with the initial concentration of 0.0050 M and the change in concentration as -x and x molar ionized.
Step 3: Use the equilibrium constant (Ka) expression to set up an equation: Ka = [C6H5COO-] * [H+] / [C6H5COOH]
Step 4: Substitute the known values into the equation and solve for x.
Step 5: Calculate the concentration of H+ ions at equilibrium.
Step 6: Calculate the pH using the concentration of H+ ions. The pH of the 0.0050 M solution of benzoic acid is 3.75.