Science Homework Help

Hi I am with these problems from General Chemistry 2

1. For propanoic acid (CH3CH2COOH, Ka =

1.3 x 10-5), determine the concentration of all species in solution (H3O+, OH-, CH3CH2COOH, and CH3CH2COO-), the pH, and the percentage of dissociation of a 0.100 M solution

3. Monochloroacetic acid (ClCH2COOH, Ka = 1.35 x 10-3) is a skin irritant that is used in “chemical peels” intended to remove the top layer of dead skin from the face and ultimately improve the complexion. Calculate the pH of a 0.10 M solution of monochloroacetic acid. 

4. Determine the pH of an HNO2 (Ka = 4.5 x 10-4) solution of each concentration. In which cases can you not make the simplifying assumption that x is too small? a) 0.500 M b) 0.100 M c) 0.0100 M