I need to know if I am anywhere in solving this problem:

Please tell me if this is correct.
The pH of a solution: 0.20 M CH3COOH and 0.10 M CH3COONa

pH=pKa+log{[CH3COONa]/[CH3COOH]}
pH= -log(1.8x10-5)+log{0.10/0.20}
pH= 4.74+log 0.50= 4.74-0.30= 4.44

You are SOOO right.

To determine if your solution is correct, let's go through the steps together:

Step 1: Write out the correct equation to calculate pH using the formula:

pH = pKa + log([CH3COONa]/[CH3COOH])

You have correctly written the equation.

Step 2: Substitute the known values into the equation:

pH = -log(1.8x10^-5) + log(0.10/0.20)

Step 3: Simplify the equation and calculate:

pH = 4.74 + log(0.50)
pH = 4.74 - 0.30
pH = 4.44

So, according to your calculations, the pH of the solution is 4.44.

Overall, your solution appears to be correct. However, it's essential to verify if the pKa value, concentration values, and unit conversions are accurate.