Calculate the average charge of H3A+ at pH 5.10 (pKa = 2.1, 3.9, 9.8). (Hint: remember that the answer must be ± 0.5 of the dominant charge.)

Calculate the pH of a buffer that contains 0.75 M acetic acid and 0.35 M acetate ion in 1 L solution. What will the pH of the buffer be upon the addition of 100.0 mL of 1.0 M HCI? (pKa of acetic acid 4.76)

Describe the preparation of 2.00 L of 0.100 M glycine buffer, pH 9.0, from glycine and 1.00 M NAOH. What mass of glycine is required, and what volume of 1.00 NaOH is required? The appropriate pK, of glycine is 9.6.

Calculate the pH of a buffer that contains 0.75 M acetic acid and 0.35 M acetate ion in 1 L solution. What will the pH of the buffer be upon the addition of 100.0 mL of 1.0 M NaOH? (Ka of acetic acid is 1.75 x 10-5 M)

Determine the fluoride ion concentration for a saturated solution of magnesium fluoride. K sp = 7.4 x 10-11

At what pressure in atm does ethane (C₂H₆) have a density of 37.2 g/L at 75.0 °C?

A monoprotic weak acid, HA, dissociates in water according to the reaction HA(aq) = H+ (aq) + A¯(aq) The equilibrium concentrations of the reactants and products are [HA] = 0.220 M, [H+] = 3.00 × 10−4 M, and [A¯] = 3.00 × 10−4 M. Calculate the value of pKa for the acid HA. pKa =

The main constituents in vinegar are water and ethanoic acid (CH3COOH). In order to determine the concentration of acid in homemade vinegar, a student titrated 25 cm3 of 001 M NaOH against the vinegar. The equation for the reaction is:                                     CH3COOH(aq) + NaOH(aq) ® CH3COONa(aq) + H2O(l)   The following titration results were obtained:   Burette readings (cm3) Rough 1 2 Final burette reading 20.10 38.90 31.40 Initial burette reading   0.10 20.00 12.50 Volume of vinegar used 20.00 18.90 18.90   (a) What volume of vinegar should be used in the calculation?                                           (b) What is the mole ratio of NaOH:CH3COOH?                                                              (c)  Calculate the number of moles of alkali in 25 cm3 of NaOH solution used.               (d) How many moles of acid were used in the titration?                                                    (e) Calculate the…

6 x 10⁻⁵¹ = (0.15 M)² [S²⁻] [S²⁻] = (6 x 10⁻⁵¹) / (0.15 M)² Calculating, we find the minimum concentration of sulfide ion required: [S²⁻] ≈ 2.7 x 10⁻⁴⁹ M. check it calcution is write

Calculate the pH of a solution containing 51 g acetic acid (K₂ = 1.75 x 10-5) and 12.3 g sodium acetate dissolved in 1 L water.